Northampton and England tighthead Kieran Brookes is set for some time on the sidelines after undergoing knee surgery.
Jim Mallinder, the Northampton boss, revealed the news after his side's Boxing Day defeat to London Irish.
Brookes has been in excellent form for Saints since his return from the Rugby World Cup, winning the club's November Player of the Month award.
The 25-year-old sustained the injury in the first half of Northampton's 9-9 draw with Racing 92 in the Champions Cup.
“Kieran Brookes has an operation on his knee a couple of days ago and he’s going to be out for quite a few weeks,” Mallinder told reporters.
"It’s a big blow. He was someone who was playing really well and our scrum was going really well, so it’s a blow.
“But that’s when the other lads have got to come in and step up.”