Saracens maintained their position at the top of the Aviva Premiership table with a bonus-point 32-20 win over local rivals Wasps at Adams Park.
Wasps, without Joe Launchbury and Matt Mullan in their pack, were second best to a strong Saracens line-up with the visitors scoring four tries through Jamie George (two), Jackson Wray and Alex Goode.
Charlie Hodgson kicked a penalty and two conversions with replacement, Owen Farrell, kicking a further penalty and conversion.
Wasps, inspired by scrum half Joe Simpson, managed three tries from Tom Howe, Jonah Holmes and Carlo Festuccia. Andy Goode did kick one penalty but missed four other kicks which prevented his side from remaining in contention.
Leicester made it eight Aviva Premiership games unbeaten as they consolidated their place in the title play-offs with a 22-16 win over Northampton at Franklin's Gardens.
And there could be fall-out for second-placed Northampton, who suffered another Premiership reversal following defeat against Sale Sharks last weekend, with Leicester's England hooker Tom Youngs having allegedly claimed he was bitten on the hand at a collapsed scrum during the first half.
Referee Wayne Barnes consulted television replays and a lengthy delay ensued, but he took no action following inconclusive re-runs.
Centre Anthony Allen's 16th-minute try - converted by fly-half Owen Williams, who also kicked five penalties - ensured east midlands bragging rights for the Tigers, as they moved third in the table above Bath despite finishing with 13 men following yellow cards for Ben Youngs and Vereniki Goneva.
Northampton, in contrast, never really got going, despite tries by Kahn Fotuali'i and substitute prop Ethan Waller, a Will Hooley penalty and James Wilson penalty, and they also saw skipper and England star Dylan Hartley make a 31st-minute exit clutching his right shoulder.
Youngster Hooley endured a difficult afternoon with the boot, missing three out of four kicks at goal before he made way for Wilson as the hour-mark approached.
Harlequins revived their play-off hopes by dispatching London Irish with the vision of Danny Care inspiring the decisive act of a hard-fought 23-9 victory at Twickenham Stoop.
England trio Chris Robshaw, Mike Brown and Care returned after being rested for last Saturday's rout by Saracens, but Quins still struggled to dispatch the Exiles.
It was only when Care floated a superb scoring pass to wing Sam Smith in the 70th minute, establishing an 18-9 lead, that Irish were beaten.
Brown, the recently-crowned player of the 2014 RBS 6 Nations, crossed late on to give the scoreline an emphatic appearance that failed to tell the full story of the Exiles' effort.
The boot of full-back James O'Connor, who kicked three penalties, kept them in the hunt until Care spied his chance to deliver the killer blow.
Gloucester moved above Exeter up to eighth as they claimed a 14-13 win at Sandy Park.
The opening 40 minutes had few memorable moments as Exeter went in at half-time 8-6 ahead after a try from wing Matt Jess and a Henry Slade penalty, with Gloucester's reply being two Rob Cook penalties.
Gloucester went ahead with Cook's third penalty before he gave the final pass for Charlie Sharples to cross out wide.
Exeter came back in the final minutes, against 13 men, through a Don Armand try but could not convert it to claim victory.