Now parked in left field, the 6-foot-5, 235-pound Polanco, nicknamed "El Coffee," was found percolating on the bases after going 4-for-4 Saturday in the Pirates' 6-4 win over Atlanta at PNC Park.
Polanco had a four-hit game in each of the last two seasons, and five hits (in 13 innings) as a rookie in 2014 in his fourth big league game.
This one happened after he started the season 1-for-14. He doubled and singled twice off veteran knuckleballer R.A. Dickey, and added a single off reliever Ian Krol. He scored twice and drove in a run, and added a stolen base for good measure.
Asked about the difficulties of dealing with the knuckleball, Polanco said he took a simple approach.
"Shorten my swing, trust my hands," he said. "Let the ball get deep. You can't get too aggressive. That ball moves too much."
Polanco laughed at his unsuccessful bunt attempt in his first at-bat.
"I missed it, and it was like 'Oh, my gosh,'" he said.
Assessing Polanco's work against Dickey, manager Clint Hurdle said, "That's what makes the game so great. The ball might have been dropping down in his hot zone. There was a lot of action on that knuckleball tonight. You saw some swings our guys took that were challenging swings. There were some right turns, some left turns on the knuckleball.
"Polanco seemed to get balls in comfortable spaces that he put the barrel on. He saw the ball the well. Sometimes it's luck of the draw, and you give the kid credit because he's got skills. Most of the balls were down on the three at-bats off Dickey, I thought he had good swings. He let the ball travel."
Nagged by knee and shoulder injuries last season, Polanco had 22 home runs and 86 RBIs while batting .258. His left shoulder remains problematic; he reported soreness after playing for the Dominican Republic in the World Baseball Classic, where he went 11-for-19 with two doubles and a home run.
"I've got to get treatment every day because it's not 100 percent," he said. "I know I'm gonna get better. I don't know when."
More certain is Polanco's spot in the batting order. Hurdle seems committed to keeping Polanco fixed at cleanup. Last season he wandered from second to third to fourth to sixth.
"You prepare every day, and your mind is set before you even come to the ballpark because you know you're hitting in that spot," he said.