JUPITER, Fla. -- Umpire C.B. Bucknor declined to shake the hand of the St. Louis Cardinals' Oliver Marmol before an exhibition game here Saturday, according to the manager, and Major League Baseball is looking into that exchange.

Marmol was upset by Bucknor's response on Saturday.

"I don't think he's good at his job, and it just shows a lack of class as a man," Marmol said after the game.

According to an MLB spokesperson, "We are aware of Mr. Marmol's comments, and the matter is under review."

Bucknor and Marmol had a confrontation during an August game in 2022, after a disputed strike call to Cardinals third baseman Nolan Arenado. Bucknor ejected Marmol, who emerged to argue -- and as the two yelled at each other, Marmol appeared to tell Bucknor that his time in the sport was done, and Bucknor yelled back that Marmol, relatively new to his position as St. Louis manager, had just gotten to the big leagues.

On Saturday, Marmol went to home plate for the exchange of lineup cards, and according to Marmol, Bucknor would not shake his hand. The other umpires -- Ron Kulpa, Angel Hernandez and Carlos Torres -- did shake Bucknor's hand. According to Marmol, others apologized for Bucknor's refusal.

"I don't think he's good at his job, and it just shows a lack of class as a man," Marmol said. "That's my thoughts on it."

Bucknor, 60, has been a major league umpire since 1996. Marmol, 36, became the Cardinals' first base coach in 2017, and was hired as St. Louis manager after the 2021 season.