Leicester's Marcos Ayerza and Harlequins' Joe Marler have been banned for two weeks for fighting in Saturday's Premiership clash.
The Rugby Football Union punishment means both props will miss crucial European fixtures this weekend.
Argentina international Ayerza is ruled out of Saturday's Heineken Cup quarter-final against Leinster.
Marler, an England Saxon, will not be available for Quins' Challenge Cup game against Wasps on Friday.
Both players will be able to feature again on 19 April.
The incident happened after 64 minutes when Ayerza appeared to headbutt Marler, who retaliated by punching his opponent.
Jeff Blackett, the chairman of the RFU disciplinary panel, said of the incident: "This was unacceptable behaviour which was captured on live TV and not something we want to see in our game.
"That said, both offences were deemed to have a low-end entry point for sanction.
"The starting point for Ayerza striking with the head was four weeks, reduced to two for his guilty plea and relatively good record.
"Marler's sanction did not alter from the two-week entry point because, despite his guilty plea, his previous disciplinary record counted against him."
, who also appeared at the RFU hearing, will receive no further punishment for his two yellow cards against Northampton.