The Sweden international, who signed from Sporting for £63M, has slowly grown into an Arsenal side who have forged a path towards the Premier League title and Champions League final this season.
Scoring five times in his last nine matches, Gyokeres adjusted to the intensity and demands of English football and is now thriving under manager Mikel Arteta.
Having scored 21 goals in all competitions this campaign, Rooney has been impressed by the 27-year-old who he thinks deserves more praise.
"I’ve said this all season and I have been criticised for saying it, but I actually really like him," Rooney said. "What he brings to that Arsenal team is that he occupies defenders. He makes them work, he makes them defend, he runs the channels.
"And what we’ve seen recently is that it’s creating more space for Eberechi Eze and for Bukayo Saka – because if one, or both centre-backs have to go and cover him and then the full-back has to cover round, when you switch the ball quickly, it creates so much space for everyone just in behind him.
"Over the last few weeks he has been showing that even more and if Arsenal go on to win the league and the Champions League, he’ll be a major reason behind it, because that’s where Arsenal have been short in the last few years.”
Arsenal legends Thierry Henry and Ian Wright reached the 20-goal mark in their debut campaign and Gyokeres has gone one step further.
The Gunners face Burnley this weekend before going head-to-head with Paris Saint-Germain in the Champions League final where Gyokeres could lead his side to their first European trophy.