That gave St Johnstone frontman May the opportunity to lead the Scots' attack and he made the most of the opportunity as he capped his first start for the Under-21s with a stunning strike in the 2-1 win over the Slovakians in Paisley.
The Perth attacker will be given the nod again for Tuesday's match in Tbilisi and McGeouch says it will take a determined effort by Watt if he is to dislodge May from the team.
McGeouch said: "We've got a lot of strikers in the under-21 squad to pick from. When Tony is playing and doing well he will score you goals. But Stevie showed on Thursday what a good player he was. He can hold the ball up, take players on and put himself about.
"He never gave the Slovakians a minute and that is great to play with.
"Can Tony get his place back? Who knows? It is up to Billy to pick his squad. Stevie got the nod for Slovakia and took his chance. He scored a goal and did really well.
"It's not a bad thing to have competition. It will mean Tony will have to up his game to get back in and Stevie will have to do better again to keep his place. They can bounce off each other. That's a good situation to have."
Watt was branded "lazy and unfit" by Lierse boss Stanley Menzo following his debut for his new club but McGeouch offered a different view.
He said: "Tony has taken the lead by going over to Belgium to try and get games and he's started well and is scoring goals. That's credit to him.
"I don't know what's going on over there, though. Tony is a good lad - a character - and we all get on well with him.
"I don't want to comment on what has been said over there but when he plays with us, he works hard and gives his all. The times I have played with him, he's been excellent, so I don't really know why certain things have been said."