Jon Lester was the focal point Saturday as he took the mound in his A’s debut, but the story of the game unfolded with Oakland’s new ace seated on the bench.

The A’s batted around in an eight-run fifth inning and coasted to an 8-3 victory over the Kansas City Royals.

That made a winner of Lester (11-7), who certainly did his part by throwing 6 2/3 innings of three-run ball. He left in the seventh to a standing ovation from an appreciative Coliseum crowd, tipping his cap after his first outing since Thursday’s blockbuster trade that sent him from the Boston Red Sox to the A’s.

For a while, it appeared Lester would have to be at his stingiest best Saturday. The A’s couldn’t generate anything off Royals lefty Jason Vargas through the first four innings. Trailing 1-0, they broke out in the fifth with a rally that tied their season-high for runs in an inning.

It was a welcome sight for manager Bob Melvin considering the A’s had been in an offensive dry spell for the past four games.