Leading the line: Jones
Kenwyne Jones has jetted off to keep his World Cup qualifying bid alive, just as Sunderland manager Ricky Sbragia admits the striker is starting to feel the effects of the season and a career-threatening injury.
Jones is looking increasingly jaded after his return from a serious knee injury four months ago and he was again substituted in his side's draw at Manchester City on Sunday.
The Trinidad and Tobago striker, who suffered cruciate ligament damage in a friendly against England at the end of last season, scored five goals in his first six appearances on his return from the injury but he has now failed to net in his last five games.
Sunderland boss Sbragia said Jones has been missing training sessions to keep him fresh for games, but he is now considering leaving him out at West Ham a week on Saturday.
After the Eastlands defeat, Jones flew to the Caribbean with team-mates Carlos Edwards and Dwight Yorke to prepare for the crucial World Cup qualifiers against Honduras and the United States.
They are not expected to return until the day before the trip to Upton Park.
Sbragia said: 'Kenwyne is tired. He's come back well for us and he's got us goals but he's had a lot of games now and maybe it is beginning to show.
'He's having to nurse himself along and we aren't seeing him on the training pitch until Friday.
Concerned: Sbragia is worried about his striker feeling worn out
'I've got a nucleus of 12 players for the next couple of weeks and we'll work and train them, give them some time off and then look to see how everyone is next Thursday.
If Jones is rested for the trip to West Ham, on-loan Marseille striker Djibril Cisse is expected to take the lone striker role in the 4-5-1 formation Sbragia prefers to use away from the Stadium of Light.
Meanwhile, Sunderland's appeal against George McCartney's dismissal against City has been successful.
The Northern Ireland international was sent off for pulling back Shaun Wright-Phillips just 15 minutes in to Sunday's game.
Early bath: McCartney receives his marching orders from referee Steve Tanner Sunderland appeal McCartney's red card for foul on Manchester City star SWPSportsmail's Star of the Season: Which player has been the top man at your club this campaign? THE LIST: 40-31 of the best defenders to have graced English football.