Round-up: Play-offs finalised as Paterson exits Saturday saw play-off places at stake in the Aviva Premiership and the RaboDirect Pro12, although perhaps the most eye-catching game was the dead rubber at the Madejski Stadium. London Irish's David Paice and Jim Hamilton of Gloucester were sent off for fighting, their second scuffle prompting a mass brawl and lots of bad feeling, and Irish won 52-18. Not that it mattered much. In the Premiership, next weekend's semi-finals will be Harlequins against Northampton (42-14 winners at home to Worcester) and Leicester (28-3 at home to Bath) against Saracens (40-22 at home to Exeter). The semi-finalists will be joined in next season's Heineken Cup by Exeter and Sale. In the Pro12, Leinster topped the table after beating the Newport-Gwent Dragons 22-18 - the European champions will host Glasgow on Saturday. The other semi-final will be between the Ospreys (18-11 winners at Aironi) and Munster, who beat Ulster, much-changed from the team that won a Heineken semi a week before, 36-8. Edinburgh, who lost to Ulster in Europe, sent the 109-times capped Scotland back Chris Paterson into retirement with a 44-21 win over Benetton Treviso at Murrayfield. Paterson, who scored his team's third try, said: "I am actually quite happy, as it is the right time to go. I am very proud of what I have achieved.