Manchester City manager Manuel Pellegrini is short of defensive options for Wednesday's trip to Sunderland following the loss of Vincent Kompany to injury.

City's influential captain suffered a hamstring problem in the latter stages of the champions' Barclays Premier League win at Southampton on Sunday and will not feature at the Stadium of Light.

That means Pellegrini will now have to field a different centre-back pairing as Eliaquim Mangala is suspended after his sending off at St Mary's.

Right-back Bacary Sagna could therefore be pressed into action in the centre or fringe player Dedryck Boyata could be drafted in alongside Martin Demichelis.

Pellegrini said: "We have Dedryck Boyata, he is working very well, we have also Martin Demichelis, we have Bacary Sagna. So we have three options. We will see which two of them will play."

Matija Nastasic, who has been out of favour this season, might have been a possibility but Pellegrini revealed that he too is currently crocked.

The Chilean said: "Unfortunately for him, he is again injured. He has had two long injuries this season. He has a muscle injury in his thigh.

"I don't know if he will be able to work with the squad for one week more so he is not an option."

City are still to learn the full extent of Kompany's problem and are waiting on the results of further assessment on Tuesday afternoon.

The champions had to finish the game on Sunday with nine men after Kompany left the field, with midfield talisman Yaya Toure filling in at the back.

That is not a situation likely to be repeated with Pellegrini preferring to keep Toure in his familiar role.

Pellegrini said: "He played in that position many years ago but I don't think it is his position in this moment.

"It was just the last minutes (at Southampton). They had very tall players and we needed a centre-back so, between him and Fernandinho, it was better for Yaya. Tomorrow I don't think he will play in that position."

City's defensive problems are a concern as they travel to a ground where they have not won since 2008 and lost on their last four visits.

Sunderland are also likely to be in good heart after holding leaders Chelsea to a goalless draw in their last outing.

Pellegrini said: "It is a tough team to play against. Because they defend very well, at home and away, it is a team that know exactly what they must do during the game. They also have a very good manager, Gustavo Poyet, who knows the Premier League, so both things make a strong team.

"We hope that this season we are going to have more luck."

Sunderland's draw with Chelsea allowed City to cut the Londoners' lead to six points with their victory at Southampton, a result which also lifted them to second in the table.

City have now won their last three in all competitions and their position is looking much healthier than prior to the November international break, when indifferent form brought heavy scrutiny.

Pellegrini said: "I said before these three games we were not playing so bad. Maybe we were making some mistakes and not getting the results we wanted.

"But we didn't change our style, we didn't lose our trust in what we can do. We will continue trying to play the same way and improving some individual mistakes and some inconsistent times during the game.

"We were never out of the fight for the title. We have to play 25, 26 more games - too many points to decide who will be the champion this year."

Former England midfielder Frank Lampard had another highly influential game at Southampton and the club are expected to extend his loan from sister club New York City, but nothing is decided.

Pellegrini has said the issue will be determined this month and will not be influenced by whether City stay in the Champions League or not.

He said: "The decision with Frank Lampard will be the same if we continue in the Champions League or if we don't continue in the Champions League. We have the whole month of December to decide."