Aji Alese is training with Sunderland's U21 squad in a bid to ease him back into the intensity of first-team football. Defender Alese has played made just one outing from the subs' bench lasting a little over half-an-hour since suffering a thigh injury in March, and that brief appearance - in the second leg of the Black Cats' play-off semi-final at Luton Town in May - saw him aggravate the problem, with Tony Mowbray later acknowledging that he was rushed back as the club struggled with a central defensive injury crisis as they pushed for promotion.

But the 22-year-old has been steadily working his way back to full fitness and he is close to joining in with Mowbray's senior squad, although for now he is training with Graeme Murty's U21 side. Alese may also play for the U21s to build up some match-fitness before he is integrated into the club's Championship campaign.

"With Aji, we've put him with the U21s for a week or so, just so that he can build up in terms of the intensity," said Mowbray. "He's been out for a long time so we have to be careful putting him back into first-time training.

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"He'll train with the U21s for a little while so he can work his way in and build himself up. Then in a week or so when he feels really confident and comfortable, he'll come back and train with us.

"So he's not too far away."

Summer signing Timothee Pembele is also edging closer to fitness, with the right-back having yet to feature since he arrived from Paris St Germain. Pembele is still recovering from the after-effects of a serious knee ligament injury he suffered last year, although he did play games in France earlier this year.

Mowbray said: "Pembele was out on the grass yesterday, doing just some work with the physio. Sidefoot volleys, running round the cones, those kinds of things.

"Again, that's telling me that he's not too far away."

Sunderland are still waiting for teenage midfielder Chris Rigg to return from international duty after he played for England in the U17 World Cup in Indonesia. The Young Lions finished top of their group but crashed out of the competition with a surprise 2-1 defeat at the hands of Uzbekistan on Wednesday.

Rigg will not be back in time to figure in this weekend's Championship game at Plymouth Argyle, but could be part of Mowbray's plans either for Wednesday night's home game against Huddersfield Town or next weekend's visit to Millwall. Mowbray said: "I'm not too sure when he'll be back exactly, he obviously won't be coming with us this weekend.

"When he gets back, he'll be back involved with us training hopefully at the start of next week. We'll of course see how he is and how he feels, how much the travelling and the games have taken out of him.

"He'll be back involved with us when he's ready, he deserves it. I've said it a lot, we have a lot of talented young players come train with us but he's just a little bit special.

"I put that down not just to his talent but his amazing attitude, which sets him aside a bit. He's got no fear not just of training with the first team but competing and engaging.

"His place in the squad is warranted, I'm delighted he's had that experience of going away to a World Cup and we'll integrate him back in as quickly as we can."