Alan Shearer explains what won FA Cup tie for Man City vs Southampton

Former Newcastle United and England striker Alan Shearer believes Manchester City's options from the bench were the key to helping them beat Southampton 4-1 in their FA Cup quarter-final at St Mary's on Sunday afternoon.

After taking an early lead through Raheem Sterling, City were pegged back right on the stroke of half-time through an own goal from Aymeric Laporte. However, three goals in the space of just 16 second-half minutes, two of which came from substitutes Phil Foden and Riyad Mahrez, sealed City's route to the last four.

Whilst the scoreline suggested that City coasted their way to the win, Southampton made life difficult for Pep Guardiola's charges. They wasted a golden opportunity through Che Adams to draw level following Kevin De Bruyne's penalty to put City 2-1 up, with it proving to be costly.

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But despite Guardiola naming just seven players on the bench, although he could have chosen up to nine, it was the quality that he was able to call upon mid-game that made the difference. Mahrez and Foden's introductions took City up through the gears and secured the win.

"They were ruthless and clinical," Shearer told BBC Sport. "They had outstanding players ready to come on and change the game.

"Southampton put up a really good fight, and they will be kicking themselves because the first two goals are really poor defensively and really bad goals to give away. At 2-1, they had a really good opportunity with Che Adams and he sticks it straight at the goalkeeper.

"And when you get these chances, against top-class teams, you have to take them, you have to punish them and Southampton didn't. The subs came on and