Sunderland manager Roy Keane has confirmed that striker Kenwyne Jones will have a knee operation this week.
The former Southampton forward suffered knee ligament damage playing for Trinidad & Tobago against England at the beginning of June.
Speaking after his side's 1-0 pre-season friendly defeat to Ajax, Keane said: "Kenwyne's going in on Monday for an operation and we'll know in 24 hours of the exact damage, so fingers crossed.
"We'll know one way or another on Monday so I'll be saying a few prayers.
"Kieran (Richardson)'s had a stiff back the last couple of days.
"There was no point risking him against Ajax but I'd be very surprised if he wasn't on the flight to Ireland with us on Wednesday."
Klaas Jan Huntelaar scored the only goal of the game for Ajax nine minutes after half-time.