Key Sunderland duo return but defensive concern: Six interesting things we noticed from pre-season training

Sunderland's players are back in pre-season training this week as they look to kick on from an excellent campaign.

Here we pick through some interesting clues from the first week back at the Academy of Light.

THE RETURN OF DB - x2!

Sunderland have moved aggressively this summer to ensure there should be no repeat of their centre-half shortage, one that probably was the biggest single factor in the team's defeat in the play-off semi final second leg at Luton Town.

Nectarios Triantis and Jenson Seelt have signed long-term deals, while there has been a big boost for Tony Mowbray this week. Danny Batth and Dan Ballard have both been fit enough to start pre-season training, giving them a good chance of starting the campaign fit and firing.

A position of weakness due to injury last season currently looks pretty strong.

A SLIGHT CONCERN TO THEIR LEFT

Where this, at this very early stage at least, a touch more concern is to the left of defence.

Dennis Cirkin was running on an anti-gravity treadmill this week, which helps players build fitness without putting too much pressure on the lower body. Cirkin missed the play-off campaign through injury and has been working hard on his recovery at the Academy of Light in recent weeks.

Aji Alese is another recovering from injury, after suffering a recurrence of the injury that sidelined him for much of the second half of last season. Alese has been back at the Academy of Light this week and so while the signs for both appear promising, it is not yet clear when they will be fully fit.

HUGGINS ON TRACK

Niall Huggins made a quicker than expected return in that play-off campaign, with the initial plan being to focus on being fully fit for this vital pre-season period.

Sunderland hope that a full pre season will help build the resilience and fitness needed to kick on from the niggling injuries that blighted his comeback last season, and so to see him working with his teammates is a very encouraging sign.

BIG CHANCES TO IMPRESS

Sunderland have bolstered their training group this week by handing well-deserved chances to impress to some of their academy players.

Zak Johnson has been playing in the England U18 side over the summer, even sharing the captain's armband with Jobe Bellingham. He will no doubt get a chance over pre-season to continue his progression, while midfielder Caden Kelly has also been with the group this week. There'll no doubt be others moving forward.

LOANEES RETURN

Jay Matete is back on Wearside, with Mowbray and Sunderland set to assess his progress over the course of the pre-season fixtures before making a firmer decision on his short and long-term future later in the window.

Bailey Wright does not appear to have been with the group this week, though that perhaps is more due to the injury he sustained while on loan at Rotherham last season, one that brought his campaign to a premature end.

BASS CHECKS IN

Bass is wanted by Leyton Orient after their first-choice goalkeeper from last season, Lawrence Vigouroux, joined Burnley.

The keeper is nevertheless back on Wearside for now and Sunderland would need to recruit additional cover before a departure could be considered.