David Moyes lamented his side's lack of fitness and experience during their 2-1 defeat to neighbours Middlesbrough at the Stadium of Light.
Patrick van Aanholt's second half goal wasn't enough to undo a first-half brace from Cristian Stuani and the Scot did admit there were few positives from the performance.
"I thought we played well in the opening 30 minutes," he said. "We lost to a really good goal. Could we have defended it better? Yes, of course. Could we have closed it down better? Of course. But don't take it away that it flew into the top corner.
"I don't know if Middlesbrough had been up the park before that goal. They have very few opportunities. We had gotten to the byline two or three times and not picked anyone out. So I don't know. Goals change games and I think goals changed the outlook of this game today."
Sunderland manager David Moyes (right) with coaching staff during the Premier League match at the Stadium of Light, Sunderland. Image: Richard Sellers / PA Wire/Press Association Images
John O'Shea was withdrawn on 37 minutes with injury and forced Sunderland to shuffle their pack to ensure they had enough bodies back defensively. Moyes says that the switch act the back unsettled his side.
"The second goal, I agree, we were poor in the second goal. But just at that period where John went off, we really needed halftime. We needed halftime after about 35 minutes to regroup. But I thought that there effort was really good to get back into the game when we were 2-0 down.
"The only thing I thought was disappointing was that our intensity was terrific but we couldn't keep it up in the last 10 minutes. That's because we've had so many young players making their debuts and Steven Pineaar who hasn't had a game in preseason.
"I've given the players credit for what they've done and I think most Sunderland supporters will understand where we're at... It wasn't an easy game for us given the nature of our team."
Sunderland have let 12 players leave the club this season, bringing in only three recruitments [Adnan Januzaj, Donald Love and Paddy McNair all from Manchester United] into the squad.
"We've lost a few players with injury but that's part of it. We'd like to add to that and we know that needs to be done anyway. There were a few young players out there that lacked Premier League experience and we were a bit wide open at times, a wee bit gung-ho.
"But that's just young defenders , young midfield players, a young fullback, so those things will take a little bit of time.
"I think we kept it going five or ten minutes after [the goal]. But when we really needed it again to go in the last five or ten minutes, we had just used up all our gas. That's something we'll have to up again because I'd like to get us to be able to go all the way to the end... It was asking a lot of us today."
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