Sunderland boss Paolo Di Canio felt fatigue caught up with his players in defeat to Chelsea.

Sunderland were well worth their 1-0 halftime lead, but blew the three points inside the opening ten minutes of the second-half.

Di Canio said: "The lads ran very, very hard and we went in at half-time 1-0 up. Fully deserved.

"The second half is difficult, because after one minute you can go blurry if you concede this goal.

"We were in the opponents' box, in a few seconds they countered and they scored their first goal.

"We concede two goals too early. We have a short time from now until the end of the season, but we're capable to build their strengths.

"Most important their attention because the two goals came from two mistakes."

Di Canio suggested the physical condition of his team should be better in a thinly veiled attack on Martin O'Neill.

"It's not the fittest team in the world," he said. "This team at this moment is not a team that can play Chelsea for 95 minutes.

"In the next few weeks we will do more work and extend the physical condition."