CINCINNATI -- The Nationals are already facing a significant injury that happened before the first pitch of Opening Day.

Starting third baseman Nick Senzel fractured his right thumb during pregame drills at Great American Ball Park. Senzel, who had played for the Reds his entire career from 2019-23, signed a one-year deal with the Nationals this offseason to play the hot corner.

Senzel was placed on the 10-day IL on Saturday, and No. 16 prospect Trey Lipscomb was called up from Triple-A Rochester to start at third base and make his Major League debut.

"The blow right before our game today really stung," manager Dave Martinez said following the Nationals 8-2 loss. "That was kind of a bad situation. He took a bad hop during BP."

Senzel had prepared in Spring Training for a turnaround season with the Nats after being non-tendered by the Reds in November -- and dealing with injuries throughout his career. But his Nationals debut is on hold. Senzel was undergoing X-rays during the team's Opening Day ceremony introductions.

"It's awful," said Martinez. "He was in a good spot, and we were in a good spot with him. He was excited for today, and just a freak accident. We're going to miss him, but he's going to work really hard to get back as soon as possible."

Opening Day starter Josiah Gray was warming up in the training room when he saw Senzel come off the field. He was among the teammates who expressed concern after the game.

"I feel terrible for him because obviously the significance of coming back here -- he had a long career here -- and for it to happen in pregame as well, it's kind of a tough blow for him," said Gray. "I definitely feel for him. I'm sure everyone's in his corner. I hope he gets back healthy soon and helps us down the road. But it's a really tough blow on the first game."

Lipscomb will join the Nats following an impressive Major League Spring Training. The 2023 Nationals Minor League Defensive Player of the Year and Minor League Gold Glove Award winner at third base turned heads in camp. He led the team in batting average while slashing .400/.455/.540 with a .995 OPS. Lipscomb, a 2022 third round Draft pick by the Nats, was reassigned to Triple-A Rochester on Tuesday, where the plan had been for him to see playing time at second base.

"I'm not going to limit his ceiling by putting a moniker on him that he's a utility player," general manager Mike Rizzo said in mid-March. "This guy's a good player. If he could help us at a single position, impact us the most, that's great. If he can impact us greater by being able to bounce around the field, I think that's great also. But he's a player. And a player's got to play, and they got to play a lot."

Utility player Ildemaro Vargas can back up third base and provide veteran mentorship to Lipscomb. He replaced Senzel in the starting lineup on Thursday following the late scratch.