Aviva Premiership Rugby leaders Leicester held off a ferocious fightback from Harlequins to clinch a hard-earned 17-13 victory as both sides ended the game with 14 men at The Stoop.
Referee Wayne Barnes showed two red cards, to Marcos Ayerza and Joe Marler, and two yellows in a white-hot thriller, but Quins will regret for some time their missed chances. Scrum-half Danny Care ensured they converted at least one of their opportunities, with fly-half Nick Evans adding eight points with the boot.
But Leicester responded through Alesana Tuilagi and a penalty try, England number 10 Toby Flood booting seven points.
Quins made a blistering start but butchered a gilt-edged try-scoring chance in the second minute. Nick Easter made a break and good link play had Leicester struggling in retreat, but Ollie Kohn lobbed a careless forward pass that let the visitors off the hook. Evans did likewise on five minutes, his first penalty of the contest sailing across the face of the goal, beyond the far post.
Leicester found their feet shortly after and it was the home team's turn to defend with Care tidying up when Tuilagi's chip-ahead bounced in goal. This was a rousing battle comprising big tackles and small margins, with Quins just shading matters during the first quarter.
Just as Bath did last week, Quins as hosts took the game to Leicester with width and at pace. But the Aviva Premiership Rugby leaders have powerful levels of absorption when it comes to defence.
Easter came closest to breaking the deadlock on 21 minutes with a thunderous run before downing the ball by the left wing flag. Referee Barnes went upstairs to the video referee who ruled that the player's left leg was in touch before he got the ball down.
Tempers flared in the heat of the contest as Harlequins were repeatedly foiled, and Leicester struggled to come to terms with opposition clearly holding no fear of them whatsoever. Referee Barnes decided Quins had pulled down a rolling maul on 27 minutes, giving Flood a chance to edge his team in front. But he hooked his penalty across the face of the target.
Justice was done on 32 minutes when Care capitalised on a flying left-wing break by Ugo Monye. Leicester brought the wing down short of the line, but the ball came back via Mike Brown to Care who spotted a gap close to the posts and dived over, Evans converting.
With Easter a driving force, Quins were causing their guests enormous problems, and they had to concede another penalty to halt an ominous maul and Evans kicked the resulting penalty. Flood missed a second penalty on 40 minutes, and half-time was a relief to the champions who could have been further adrift.
Whatever was said during half-time, Leicester were aflame from the restart and had chopped the lead to three points in as many minutes. Craig Newby stormed off a lineout towards the line, Leicester retained possession from the ruck and when the ball reached Tuilagi on the left wing he squeezed in by the flag, Flood converting.
Quins were in serious trouble just 10 minutes into the second period when Leicester forced three penalties in succession from scrums close to the home side's line. Barnes then sin-binned Will Skinner for pinching the ball when he thought it was out – and binned prop Mark Lambert minutes later for collapsing.
Down to 13 men, the next scrum was too much to handle for Quins and Barnes awarded the inevitable penalty try. Evans had a chance to reduce the deficit but missed a penalty – then the game exploded on 64 minutes when Ayerza head-butted Marler who responded with a flurry of punches and both were sent off.
Evans kicked another penalty on 66 minutes as Quins got their sin-binned men back on the field. But when he got the chance to regain the lead, Evans' kick faded inches in front of the bar and Flood made no such mistake on 73 minutes to give Leicester a cushion they never relinquished.