TONY MOWBRAY will be making “three or four” changes again tomorrow evening as Sunderland’s crammed Championship schedule continues with a trip to Rotherham United.

The Black Cats boss made three alterations to his starting line-up at QPR last Tuesday, and opted for another three changes as Sunderland were pegged back by Bristol City’s stoppage-time equaliser at the Stadium of Light at the weekend.

Tomorrow’s trip to the New York Stadium is the Wearsiders’ fourth game in the space of ten days, and Mowbray admits that more tinkering will be needed to ensure his players can cope with the workload that is being demanded of them at the moment.

“We’re trying to get the balance right,” said the Sunderland boss, whose side currently sit in fifth position in the table. “We’ve made three changes in the last couple of games, and there’ll probably be another three changes for Rotherham.

“There might be for the weekend again, but then after that, we’ve got a week of going Saturday to Saturday where hopefully we can recover a bit.

“At this moment, we’re not really tinkering because of the opposition, the changes are about our team and who we think might need a bit of a rest.”

In the last month or so, Mowbray’s selection changes have not really impacted on Sunderland’s back four, with Dan Ballard and Danny Batth established as the first-choice centre-half pairing and Trai Hume and Aji Alese seemingly nailed down in the full-back spots.

The same back four has started for the last seven matches, but Mowbray has revealed that he is set to make defensive alterations tomorrow. Luke O’Nien is an option to start at centre-half, while Dennis Cirkin could replace Alese at left-back.

“There will be changes in the defence,” said Mowbray. “I probably shouldn’t be telling you that, but there will be. I see the players after the game, and they can barely move, they are absolutely exhausted with the effort that they’re putting into football matches. Then, you ask them to go and train for a couple of days after and then do it again.

“They’re not necessarily going to drop off because they can go again, they can keep pushing themselves beyond what they feel is their maximum. I feel we could keep doing that, but I also feel that we’ve got a squad of players where we can cover for a few players.

“Hopefully, that doesn’t weaken us, other than maybe the consistency aspect, particularly when you’re talking about defenders. The understanding builds up within a defence, you get to know each other’s strengths and weaknesses, so when you start tinkering with that, there can be a bit of uncertainty about what somebody’s going to do when the ball goes into a certain area.

“That’s probably why there’s sometimes a bit of resistance about changing the backline if it’s doing well, but then sometimes you just have to accept that a change or two is required.”