By Brandon Longo

PHILADELPHIA (CBS) — Citizens Bank Park roared with boos when Phillies manager Gabe Kapler was introduced during the home opener ceremony on Thursday.

An embattled Kapler has been taking criticism for heavy use of his relievers last weekend in Atlanta — and a mix-up that led to him summoning one who wasn’t even warmed up. “It’s my responsibility,” Kapler said before the game. “I spent the last 48 hours digging into how to improve our bullpen usage and be really good at it going forward.”

The criticism of Kapler may have also made its way into the clubhouse.

“We’ll be OK … We just need the manager to get out of the way,” an anonymous Phillies player told Jon Heyman of FanRag Sports.

Kapler is one of three managers (Ryne Sandberg, Pete Mackanin) since the Charlie Manuel era.

The Phils are 1-4 on the season as they kick off their series against the Marlins on Thursday.