The Pittsburgh Pirates suffered a serious blow to their starting lineup when center fielder Oneil Cruz was placed on the 10-day injured list Wednesday, retroactive to Monday, with non-displaced fractures of the fourth and fifth metacarpal in his left hand.

A source told TribLive that Cruz is expected to miss four to six weeks. The Pirates recalled outfielder Billy Cook from Triple-A Indianapolis to replace Cruz on the active roster. They also placed catcher Henry Davis on the major league paternity list and recalled catcher/first baseman Rafael Flores Jr., who joined the team via the taxi squad Tuesday.

Flores batted .207 with six doubles, two triples, four home runs, 27 RBIs and 21 runs scored in 53 games at Indianapolis this season. Catcher Joey Bart, out since May 10 with a left foot infection, began a rehabilitation assignment Wednesday at Low-A Bradenton.

The 27-year-old Cruz is batting .264/.350/.472 with 10 doubles, 14 home runs and a team-leading 44 RBIs, 45 runs scored and 21 stolen bases in 64 games this season. He also is tied with Philadelphia Phillies designated hitter Kyle Schwarber for the MLB lead with 98 strikeouts.

Cruz injured his hand when tagged by Atlanta Braves catcher Austin Wynns on a headfirst slide into home plate in the fourth inning of Saturday’s 6-3 loss at Truist Park. Cruz continued to play, drawing a walk and striking out in his final two plate appearances.

He did not start Sunday but entered the game in the ninth inning as a pinch runner for Brandon Lowe, who hit a leadoff single in the 3-2 loss. Cruz advanced to third on Jake Mangum’s single but was stranded when Endy Rodriguez struck out to end the game.

Cruz was scratched from the starting lineup Tuesday for the series opener against the Los Angeles Dodgers and replaced in center field by Jake Mangum. It leaves the Pirates without two of their fastest players and most dangerous baserunners, as rookie shortstop Konnor Griffin also is on the 10-day injured list with a right elbow strain.