The Red Devils endured a difficult season, going without a trophy for a fifth straight season and finishing sixth in the Premier League with their all-time lowest points tally.
However, at 37, Ronaldo was the team’s top goalscorer which, combined with De Gea’s good performances in goal, offered a small ray of sunshine in an otherwise miserable season for the club.
Cavani, who is leaving Old Trafford after two years, thinks United are “inconsistent” and says only two players appear regularly.
Speaking to ManUtd.com, he said: “I think the team has been a bit inconsistent this season overall throughout the season.
“I don’t think we’ve ever found that… how would you put that… that consistency throughout the season, either as a group as a whole or on an individual basis.
“But I think the standout player for us this season and someone who has shown a bit more consistency, has played well regularly and has always been there for us, was Cristiano (Ronaldo).
“After him comes David (De Gea) as he was also one of the most consistent players in the squad so this time together they were the most consistent and best players in the squad of our season.”
Cavani’s departure leaves United with few striker options ahead of next season with Marcus Rashford upset and Anthony Martial out of favor at the club.
Since his return to the Manchester giants last summer, Ronaldo has performed well in terms of goals but needs to be complemented with a second centre-forward given his age.
The Red Devils have been linked with moves for Benfica’s Darwin Nunez and RB Leipzig’s Christopher Nkunku as new manager Erik ten Hag looks to begin his tenure at the club.
However, without the offer of Champions League football, United will struggle to beat their rivals in such signings.
Meanwhile, De Gea has cemented his position as Old Trafford’s No 1 goalkeeper after battling Dean Henderson.
But will be challenged by a new No. 2 next season, with Lee Grant announcing his retirement and Henderson reportedly seeking a loan switch.
MORE : Edinson Cavani confirms Manchester United exit with final message to club and fans
MORE: Manchester United have said they will have to pay £100m to sign Benfica star Darwin Nunez this summer
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