Williams, 23, has been one of the few bright spots on a Phillies team on pace to lose triple-digit games. Through his first 45 Major League games, he is hitting .283 with eight doubles, three triples, seven home runs, 26 RBIs and an .840 OPS in 185 plate appearances.

He has been one of the most productive rookies in the National League since the Phillies called him up on June 30. Since then, Williams entered Tuesday ranked fourth among NL rookies in hits, fifth in RBIs, batting average and on-base percentage and sixth in slugging percentage.

Williams’ homer came on a 2-2, 97-mph fastball on in the insider corner from Marlins right-hander Jose Urena.

“I think that pitch maybe was a ball,” Williams said. “It’s just my hands. My hands are quick. That’s a confidence booster, knowing I can get to that. Especially a guy throwing that hard.”

But Marlins center fielder Christian Yelich ensured that was it for Williams. The Phillies’ outfielder forced Yelich to make a leaping grab in front of the center-field fence in the fifth inning to rob him of home run No. 8.

“I’m upset about that one that was robbed,” Williams said. “I’ve robbed two homers this year: one in Spring Training and one in [Triple-A] Lehigh [Valley]. Now I know how other people feel. It would’ve been my first multi-homer game in the bigs.”