Manuel Pellegrini has expressed his concern at his side's failure to get on the scoresheet for the second home game in a row following Manchester City's surprise 2-0 defeat at home to Middlesbrough in the FA Cup.

Thee hosts had numerous chances to score but were kept at bay by a resolute Boro rearguard, with visiting keeper Tomás Mejías pulling off a string of fine saves in the opening 45 minutes and former Chelsea midfielder Frank Lampard hit the post from range in the second-half.

"We had six or seven clear chances to score - we played well in the first-half, he declared. After they scored, we were disordered, they had a counter attack and they scored again late on. Before they scored, we did well - after that, I think Middlesbrough deserve to continue in the cup as they played very well. It's a strange game to analyse - there were two games in one. I am concerned, not because of Chelsea but because we didn't score in our last two home games.

We conceded two goals in four of our last five home games; we need to recover our performances, both attacking and defending."

However, the Chilean refused to place the blame for the defeat on fatigue following a midweek trip to Abu Dhabi to play in a friendly against Bundesliga strugglers Hamburg.

"The problem is we’ve had to change our style of play – we had no strikers for a month,” he stated. "After that, they’re coming back and maybe they needed time to reach their best performances but we have to retain the way we normally play."

“We will start working towards the Chelsea game now… we have no problem with motivation.”

His opposite number Aitor Karanka was unsurprisingly delighted with his side's performance, and dedicated the victory to the 5,000-strong travelling army which made the journey from Teesside.

“I’ve only been a manager for 14 months and we were so close to beating Liverpool [in the Capital One Cup] but we lost on penalties - today, we beat one of the best squads in the world,” Karanka beamed, also calling the game the best of his short managerial career.

“Today we had a Champions League team to play against, so I knew it was going to be very difficult. The only chances City had in the first half were from our mistakes but we fixed them in the second half and we were better with the ball. We didn’t lose the ball in the second half in the same way we lost it in the first.”