Saracens kept up the pressure on Northampton Saints at the top of the Premiership table as they downed struggling Exeter Chiefs 23-10.
The boot of the ever-reliable Charlie Hodgson was also pivotal to Saracens' win as the veteran No.10 kicked a succession of second-half penalties to keep Exeter at arm's length.
Exeter started like an express train at the Allianz Park and took advantage of multiple Saracens' changes due to the international weekend as they raced into a 7-0 lead.
Centre Ian Whitten scored after just nine minutes, with the ever-reliable Gareth Steenson adding the extras as Saracens struggled to get going.
Despite dominating possession and territory, Saracens failed to get themselves on the scoreboard as countless forays into the opposition 22 saw them come up empty-handed.
Needless handling errors and an inability to find the final pass saw Saracens frustrated, with exiled England man Chris Ashton among the guilty party for the home side.
Even the prolific Hodgson missed his penalty attempt on 14 minutes as title-challengers Saracens struggled to break down resolute Exeter defending.
The removal of hooker Jack Yeandle in the opening quarter through injury seemed to rock the Exeter set-piece, with young England No.2 Luke Cowan-Dickie coming on as his replacement.
And after 33 minutes Saracens pressure final told as giant prop Johnston bustled his way over the tryline with the help of Mouritz Botha to give the home side a foot in the game, with Hodgson expertly adding the extras.
Saracens lost against London Irish in their last Premiership home fixture earlier this month and Mark McCall's men ensured there was to be no repeat performance, avoiding an unwanted statistic of losing two at home on the bounce for the first time since 2006 in the process.
Exeter Chiefs have not won on the road since round seven but their challenge against Saracens showed no signs of unravelling in the second-half as Steenson kicked the visitors back in front with a penalty on 47 minutes.
But the Chiefs, who have lost their last four games, committed a needless error straight from the restart, which saw Saracens handed a penalty, kick for touch and from the resulting lineout Brits was driven over the line.
Hodgson again added the extras as Saracens responded immediately to Exeter's penalty to get their noses back in front 14-10 with 30 minutes remaining.
There was a sizeable hold up in play just seconds later as England lock Botha suffered a head injury and was stretched off the field and replaced by veteran Steve Borthwick.
Saracens further extended their lead after 54 minutes as Exeter were penalised for a deliberate knock-on and Hodgson kicked the resulting penalty to take the score to 17-10.
And the former England flyhalf turned the screw further just three minutes later as he kicked his second penalty in quick succession.
Saracens dominated possession in the final quarter but the home side's England trio of Joel Tomkins, Brad Barritt and Ashton were unable to find space to add a third score of the afternoon.
Exeter refused to throw in the towel but Hodgson ensured the scoreboard kept ticking over in Saracens' favour as he added a further penalty to make the final score 23-10 late on.
Tries: Johnston, Brits
Con: Hodgson 2
Pen: Hodgson 2
Saracens: 15 Ben Ransom, 14 Chris Ashton, 13 Joel Tomkins, 12 Brad Barritt, 11 Chris Wyles, 10 Charlie Hodgson, 9 Richard Wigglesworth, 8 Ernst Joubert (captain), 7 Kelly Brown, 6 Jackson Wray, 5 Mouritz Botha, 4 George Kruis, 3 James Johnston, 2 Schalk Brits, 1 Richard Barrington.
Replacements: 16 Jamie George, 17 Nick Auterac, 18 Matt Stevens, 19 Steve Borthwick, 20 Jacques Burger, 21 Neil De Kock, 22 Marcelo Bosch, 23 Tim Streather.
Exeter Chiefs: 15 Phil Dollman, 14 Fetu'u Vainikolo, 13 Ian Whitten, 12 Henry Slade, 11 Matt Jess, 10 Gareth Steenson, 9 Dave Lewis, 8 Dave Ewers, 7 Ben White, 6 Tom Johnson, 5 Damian Welch, 4 Dean Mumm (captain), 3 Hoani Tui, 2 Jack Yeandle, 1 Ben Moon.
Replacements: 16 Luke Cowan-Dickie, 17 Carl Rimmer, 18 Alex Brown, 19 Don Armand, 20 Kai Horstmann, 21 Haydn Thomas, 22 Ceri Sweeney, 23 Jason Shoemark.
Referee: Wayne Barnes
Assistant referees: Nigel Carrick, Paul Burton
TMO: Rowan Kitt
Leicester Tigers 20-15 London Irish
Tries from Ben Youngs, Lugovi'i Mulipola and Niki Goneva saw Leicester Tigers grind out a 20-15 victory over London Irish and move into the top four of the Premiership.
The Tigers have now lost just one of their last eight matches but Irish, who scored five penalties, will rue their inability to cross the try-line in the closing stages.
For Leicester, it was another gritty victory and after Harlequins slipped up at Gloucester on Saturday, Richard Cockerill's men leapfrogged the Londoners in the Premiership table.
London Irish came into the match seeking a fourth straight Premiership win and they made a perfect start when they were awarded a penalty straight from Shane Geraghty's deep kick-off.
Australia's James O'Connor made no mistake from in front of the posts for a 3-0 lead inside the opening minute.
Leicester swiftly grew into the game however and quickly exerted their influence at the scrum, and on seven minutes the Tigers were awarded a penalty deep in Irish territory.
Leicester opted for another scrum, and the decision paid dividends with scrum-half Youngs picking up and darting over in the corner.
Owen Williams, preferred at flyhalf to Toby Flood, missed the difficult conversion however and while O'Connor missed one penalty, he quickly made amends with another to give the Exiles a 6-5 lead on 16 minutes.
While the Tigers were dominant at the set-piece, it was Irish who looked more threatening with ball in hand and the hosts extended their advantage on 25 minutes when, after the Exiles went through the phases and then embarked on a driving maul, O'Connor slotted a simple penalty.
Irish's inability to live with Tigers' power upfront was to prove costly again however and tighthead prop Mulipola forced his way over from a Leicester maul - referee JP Doyle awarding the try after consulting the TMO.
Williams missed the conversion from also the same place as his first effort but things got worse for London Irish when centre Eamonn Sheridan was sent to the sin bin on 37 minutes for taking out Tigers fullback Mathew Tait in the air.
After the break, Leicester were able to make their extra man pay when Fijian flyer Goneva broke down the right and burst through O'Connor's tackle for the Tigers' third try.
Williams nailed the conversion and when he was on target with a penalty, after more problems at the scrum for the Exiles, the Tigers were threatening to run away with it.
London Irish did have the chance to respond immediately after Williams fielded the restart and a fine chase from Sheridan forced Jordan Crane into the infringement but O'Connor's effort from the tee was not given, even if he thought otherwise.
He made amends on the hour mark however with his fourth penalty of the match and while Leicester tried to keep the play in the Irish half, the hosts continued to carry the fight to their opposition, boosted by the emergence of England winger Marland Yarde from the bench, returning from a lengthy injury lay-off.
With just over ten minutes to go, Irish pressure was rewarded with another penalty when replacement Thomas Waldrom was sent to the sin bin but again O'Connor's radar was off and the Tigers maintained their eight-point cushion.
Still Irish kept coming however and more indiscipline from the visitors crept in and when they were penalised for not releasing, Ian Humphreys took over the kicking duties and brought the hosts to within five on 71 minutes.
With their extra man, Irish scented blood and a superb flowing move, through numerous phases saw Irish move from one end of the field to the other but Ofisa Treviranus knocked on with the tryline gaping, ensuring replacement Jebb Sinclair's try was ruled out, letting the Tigers off the hook.
For London Irish:
Pens: O'Connor 4, Humphreys
Tries: Youngs, Mulipola, Goneva
London Irish: 15 James O'Connor, 14 Alex Lewington, 13 Eamonn Sheridan, 12 Shane Geraghty, 11 Andrew Fenby, 10 Ian Humphreys, 9 Darren Allinson, 8 Ofisa Treviranus, 7 Blair Cowan, 6 Kieran Low, 5 Nic Rouse, 4 George Skivington, 3 Jamie Hagan, 2 David Paice, 1 Matt Parr.
Replacements: 16 Jimmy Stevens, 17 John Yapp, 18 Leo Halavatau, 19 Jebb Sinclair, 20 Gerard Ellis, 21 Topsy Ojo, 22 Marland Yarde, 23 Sean Kennedy.
Leicester Tigers: 15 Mathew Tait, 14 Blaine Scully, 13 Vereniki Goneva, 12 Anthony Allen, 11 Adam Thompstone, 10 Owen Williams, 9 Ben Youngs, 8 Jordan Crane, 7 Julian Salvi, 6 Jamie Gibson, 5 Louis Deacon, 4 Ed Slater (captain), 3 Logovi'i Mulipola, 2 Rob Hawkins, 1 Marcos Ayerza.
Replacements: 16 Neil Briggs, 17 Boris Stankovich, 18 Fraser Balmain, 19 Steve Mafi, 20 Thomas Waldrom, 21 David Mele, 22 Matt Smith, 23 Toby Flood.
Referee: JP Doyle
Assistant referees: Roger Baileff, Paul Dix
TMO: David Sainsbury
Northampton Saints 22-16 Newcastle Falcons
Newcastle Falcons picked up what could be a crucial losing bonus point through Noah Cato's try in a spirited but ultimately doomed fightback against Premiership leaders Northampton Saints, going down 22-16.
Trailing 19-6 at the interval, the Falcons limited Saints to just three points after the break and when Cato dotted down on 77 minutes, Joel Hodgson slotted the crucial conversion to seal a valuable point.
Tries in the first half from James Wilson and Tom Stephenson saw Saints threaten to run riot but Rory Clegg chipped away from the tee and an improbable victory became a possibility when Cato went over.
It wasn't forthcoming but having also picked up a bonus point last time out against Harlequins, the Falcons are now 12 points above bottom side Worcester Warriors.
The league leaders took just seven minutes to break the deadlock through James Wilson's try and the Falcons were masters of their own downfall, Matt Thompson's short line-out was ruled illegal and Kahn Fotuali'i's quick tap led to the New Zealander going over in the corner.
Stephen Myler missed the difficult conversion however, and Rory Clegg posted an immediate response from the tee on ten minutes after an offside in the 22.
Saints remained on top however, and Tom Stephenson added their second try with a superb individual score on the quarter-hour, beating two defenders to touch down under the posts for to open his Premiership account - Myler converting.
Clegg hit back with another straight-forward penalty in front of the posts four minutes later, with the Saints penalised for holding on.
He missed a chance of a third on 25 minutes however, slicing wide from a difficult angle after the Falcons had turned over possession deep in the Saints' half.
A scrum against the feed on the half-hour added to the hosts' troubles however and the pressure paid off with Wilson adding his second on 32 minutes.
Jamie Elliott showcased his clever footwork to break the line, before Myler's offload and George Pisi's unselfish pass set up the fullback.
Myler added the extras, assisted by a strong wind, to give the Saints a commanding 19-6 half-time lead.
Mark Wilson's inside pass allowed Chris York to gain valuable yards and an offside by the Saints gave Clegg a simple kick to reduce the deficit on 58 minutes.
Myler hit back with a straightforward kick off his own on 62 minutes though, taking full advantage of Newcastle indiscipline on their 22.
Cato set up a nervy finale for the league leaders however, intercepting George Pisi's pass on the right-wing and running in a 40-yard try on 77 minutes.
Hodgson's kick reduced the deficit to within a converted score and the Falcons pack forced a line-out with a minute remaining to regain possession but there was no way back for the hosts.
Pen: Clegg 3
Tries: Wilson 2, Stephenson
Con: Myler 2
Newcastle Falcons: 15 Alex Tait, 14 Noah Cato, 13 Gonzalo Tiesi, 12 Jamie Helleur, 11 Ryan Shortland, 10 Rory Clegg, 9 Mike Blair, 8 Ally Hogg, 7 Will Welch (captain), 6 Mark Wilson, 5 Fraser McKenzie, 4 Scott MacLeod, 3 Oliver Tomaszczyk, 2 Matt Thompson, 1 Rob Vickers.
Replacements: 16 George McGuigan, 17 Gary Strain, 18 Kieran Brookes, 19 Sean Tomes, 20 Chris York, 21 Warren Fury, 22 Joel Hodgson, 23 Adam Powell.
Northampton Saints: 15 James Wilson, 14 Ken Pisi, 13 George Pisi, 12 Tom Stephenson, 11 Jamie Elliott, 10 Stephen Myler, 9 Kahn Fotuali'i, 8 Sam Dickinson, 7 Phil Dowson (captain), 6 Calum Clark, 5 Christian Day, 4 Samu Manoa, 3 Salesi Ma'afu, 2 Mike Haywood, 1 Alex Waller.
Replacements: 16 Ross McMillan, 17 Ethan Waller, 18 Gareth Denman, 19 GJ van Velze, 20 Ben Nutley, 21 Alex Day, 22 Glenn Dickson, 23 Ben Foden.
Referee: Andrew Small (Eng)
Assistant referees: Robin Goodliffe, Ashley Rowden
TMO: Trevor Fisher