Watkins has been a standout performer since the start of the year, scoring 16 goals in 31 games across all competitions.
In a post-match interview with Sky Sports, McGinn praised Watkins, even joking that he wished the striker was Scottish.
"I wish he was Scottish," McGinn said. "He was disappointed in March, but if it gave him a boost, he's certainly responded well."
"We're fortunate to have him," McGinn continued. "What he's done for this club over the past few seasons has been impressive. He might have just made it onto the plane, and hopefully he can carry that momentum into the next game."
