Middlesex's former England bowler Toby Roland-Jones is set to miss much of the season after injuring his knee.
The 33-year-old was due to have surgery on Thursday to repair a cartilage tear he suffered on Tuesday ahead of his side's County Championship match against Gloucestershire.
"This is horrible news for Toby," head coach Stuart Law told the club website.
"It is really unfortunate to lose a player of Toby's ability and presence both on and off the field."
Law added: "We hope the post-surgery news is positive but his absence does create opportunities for other players to shine. We all wish him a speedy recovery."
Roland-Jones returned to action for the first time since September 2019 earlier this month having had a shoulder injury.