So said boss Grant McCann after the 26-year-old hot shot bagged his 22nd goal of the season in the 3-0 win over Southend United.
Marquis’s goals and all-round game have become integral to Doncaster’s promotion bid – which was underlined on deadline day when Rovers rejected bids believed to be £1.25m and £2m from Sunderland for their star striker.
The in-form frontman has featured in 38 of Rovers’ 41 games this season and has netted 12 times in his last 17 games in all competitions.
McCann hailed Marquis’s durability and dedication following Tuesday night’s victory over the Shrimpers.
“It’s phenomenal [that he rarely misses games],” said McCann.
“He puts his body in front of people, he gets whacks, he gets knocks. He’s a tough boy, he really is.
“He can hold his own against anyone, any centre half in this league. He’d be horrible to play against, I know that much.
“He lives his life right away from the football club.
“On a Monday morning when we train he’s the best trainer again, running around and working hard.
“That’s him, that’s John. That’s why he’s got the number of goals he’s got.”
Marquis headed home James Coppinger’s cross to set Rovers on their way to a 12th win in their last 18 games.
“John was outstanding again tonight,” said McCann. “That’s another goal for him, 22 goals now.
“I think he hit the post, the bar and had another one cleared off the line.
“He’s so dangerous. He gets into some unbelievable positions and we’re getting the players to find him now.”