Sunderland striker Darren Bent could be set for a lengthy spell on the sidelines with the hamstring injury that forced him to miss Saturday's 2-0 win against Stoke City.
The former Tottenham forward seems certain to miss Tuesday's game against his former team with the problem he sustained in training.
To add to boss Steve Bruce's woes, John Mensah is also set for a lay-off after injuring a shoulder against the Potters.
Bruce said in the build-up to the Spurs game:"It's been a tough week mentally and we've got Chelsea away on Sunday – I might freshen things up tomorrow night.
"We've got Titus (Bramble) to come back in too (after serving a suspension) and he'll obviously come into the reckoning.
"John Mensah's hurt his shoulder and that's more bad luck for him.
"It's a shame because he's trained fully for the last three or four weeks and was desperate to get back into the team.
"We're sending him for a scan and hopefully the damage won't be too bad."