The 20-year-old frontman struck his 50th goal as a professional in just 73 games in Sunday’s 1-0 win over Hearts in Perth.
His reward for his incredible scoring record was a call-up to the Scotland Under-21 squad that will face England at Bramall Lane next Tuesday.
May has already notched the crucial goal which knocked Norwegian heavyweights Rosenborg out of the Europa League this season.
Team-mate MacLean believes the striker is ready to shoot his way to a full call-up after bulking up his skinny frame following loan stints with Alloa and Hamilton.
MacLean said: “Stevie has been fabulous since he has come back into the side. He’s been a breath of fresh air. He is scoring goals – which he always does – but he has also added something to his game. Hopefully the two of us can continue to build our partnership.
“He has bulked up as well and he looks ready to play in the SPFL (Premier League). Hopefully he can keep going and get some more goals.
“He’s a young guy and I’m sure he can on and play at the highest level and even for Scotland.”