With a few throws left over from his abbreviated start Friday night against the Oakland Athletics, rookie Shelby Miller threw an extended bullpen session Sunday morning as he searched for his fastball command.

“I looked back at the video again and the ball was running, it just was a straight four-seam (fastball) with no life,” Miller said. “I’m just pushing it.”

Miller threw 35 pitches in a between-start workout that usually involves throwing 20. He spent the time focusing on his mechanics. Pitching coach Derek Lilliquist spotted that Miller was rushing how quickly he gets the ball out of his glove on his delivery, and ace Adam Wainwright studied the rookie from several angles during the bullpen throws.

Miller feels that he has accelerated his arm out of the windup and interrupted his timing and ability to control his fastball. He allowed five runs in 1 2/3 innings of work Friday and said his fastball was the culprit. So deceptive early in the season that teams like Milwaukee praised its life, it has gone flat or lacked accuracy in recent starts.

Miller has lost three of his last four games and allowed nine runs in his past 7 1/3 innings.

“It isn’t going to take much time to get back to normal,” said Miller, who is set to start Wednesday against the Angels. “This is going to be the longest four days ever.”