How can Ronaldo play well if in the last few weeks Ronaldo has only play 207 minutes in the EPL and 171 minutes in the Europa League, this will make it difficult for Ronaldo to perform optimally.
Of the several matches play by Manchester United, in the Europa League the match against FC Sheriff became an important momentum because Ronaldo was believed to have play for 81 minutes, that including Ronaldo's second most playing minutes this season.
If Ronaldo should be given more chances to play in every game like last season I'm very sure he will score more goals. The game Manchester United played against arsenal in the EPL Ronaldo was brought into the field in late hours of the game, even if he did not score goals in that game but performed very well. I really understand why Ronaldo haven't scored more goals this season, he never had the privilege to have good time in all the games.