Rooney's contribution at the Euros has been the subject of much debate in the press but there remains a feeling that the striker is approaching his peak with regards to his United performances.
"Where Wayne has improved is his consistency in scoring goals," said the boss. "He got 32 goals last season and that has made a difference to his game. It's difficult to say whether he is at a peak or not but his goalscoring has certainly given us more of a reward."
In terms of the striker's performance at the European Championship, the Scot was not surprised that the Merseysider appeared to be struggling for full fitness after being forced to sit out the opening two games of the tournament.
"We know him better than anybody," he explained. "If Wayne misses couple of games, it takes him three or four to come back. He needs a lot of football. He’s a big lad. He is stocky and he needs a lot of games.
"I always thought it was a bit of a difficult one really. He’d not played since his last game on 13 May until he played the third game of the Euros more than a month later. I don’t know what his stats were but he certainly didn’t look as sharp as normal. When he played one big game in four days and then had to play another one, that is very hard."