Call it a statement game. Call it a signature victory. Or just call it a nice way to end a tough, oft-interrupted road trip.

Alex Gordon’s grand slam capped a five-run 10th inning Thursday afternoon that carried the Royals to an 8-3 victory over the Detroit Tigers at Comerica Park.

Gordon’s blast — and it was that — came after James Shields matched Tigers ace Justin Verlander in exactly the sort of performance the Royals envisioned when they acquired him in the offseason trade from Tampa Bay.

“It’s amazing what Shields does,” Gordon said. “You know what? They always talk about Big Game James Shields, but we didn’t realize what that was until we got him over here with us.”

Shields got a no-decision, but his outing enabled the Royals to stare down a long-time nemesis in Verlander.

“He matched him pitch-for-pitch,” first baseman Eric Hosmer said. “It doesn’t matter if he gives up a couple of runs early, he’s still going to get deep into games. That’s exactly what we needed.”

Lorenzo Cain started the winning rally by ripping a one-out double to center against Phil Coke, who then walked Mike Moustakas. A first-pitch wild pitch to Jeff Francoeur moved the runners to second and third.

That led to an intentional walk to Francoeur, which set up a force at every base, and shifted the spotlight to George Kottaras, who entered the game an inning earlier after Salvy Perez exited for a pinch-runner.

“He is going to give you a professional, no-panic at-bat in those situations,” manager Ned Yost said. “I turned to Gordie and said, ‘They’re going to have to throw this kid three strikes or they’re going to end up walking him.’”

That’s exactly what happened, and the Royals led 4-3.

The Tigers brought in Darin Downs, who induced a grounder from Chris Getz that resulted in a force at the plate before Gordon rocked a 2-0 pitch for his first career grand slam.

The ball sailed through the rain into Miguel Cabreraland — the hedges beyond the center-field wall.

“He’s the only one I’ve seen go out there until Gordo did it,” Hosmer said. “Initially, off the bat, everyone was just hoping it would get over (Austin Jackson’s) head.

“Then the ball kept going and we just went, ‘Wow!’ He crushed that ball.”