WEST PALM BEACH, Fla. -- Matt Barnes has an opportunity with a new team, and he is eager to get back to his old self.

The veteran righty reliever joined the Nationals on a Minor League contract with an invitation to Major League camp. His nameplate with a No. 41 was displayed in the clubhouse between Josiah Gray and Jake Irvin on Tuesday morning.

¡°It¡¯s a young organization with some talent and guys who are excited to play,¡± Barnes, 33, said before the Nationals¡¯ 4-3 win Wednesday over the Red Sox at CACTI Park of the Palm Beaches.

¡°They've shown success in the very near past. I really was just excited to get into an organization where hopefully I could come in and help and maybe provide some wisdom and get us back to the postseason and compete for a chance to win.¡±

The Nationals have a vacancy to fill in the bullpen after it was determined right-hander Mason Thompson will undergo Tommy John surgery on Friday. Nationals manager Dave Martinez estimates there are two to three openings in the ¡®pen, and Barnes is a candidate to cover late innings.

"He attacks hitters,¡± Martinez said. ¡°He¡¯s got a really, really good slider. Good fastball, sneaky. But he knows how to get outs. He¡¯s been in high leverage situations, so we could definitely use him in that seventh, eighth, ninth inning if need be."

Barnes pitched the first nine years of his career with the Red Sox, including winning the 2018 World Series and earning his first All-Star selection in 2021, during which he went 6-5 with a 3.79 ERA and 24 saves. The following season, though, he finished 0-4 with a 4.31 ERA and eight saves.

Boston traded Barnes to Miami for Richard Bleier -- who also is a non-roster invitee in Nats camp -- ahead of the 2023 season. After going 1-0 with a 5.48 ERA in 24 relief appearances, Barnes had season-ending surgery for a hip impingement last July.

¡°It¡¯s been tough physically with him, right?¡± said Red Sox manager Alex Cora. ¡°But I do believe, stuff-wise, when he's healthy he's good. That breaking [ball] plays more, the fastball -- obviously when he's at certain velocity, he's dominant. So hopefully it works out with them.¡±

Barnes said his hip feels ¡°great.¡± His prep this offseason included throwing at his alma mater, University of Connecticut, indoors -- ¡°It's a little chilly out there,¡± he noted. Barnes estimates he has not ¡°had spikes on in eight months.¡± He hopes to get off a dirt mound as soon as Thursday, throw a bullpen session in the coming days and pitch in a game next week to show the Nationals how he could help the club.

¡°First and foremost, [I want to show] that I'm healthy and feeling good,¡± Barnes said. ¡°I feel like I¡¯ve got things to still offer this game and offer this organization and team, and that I'm back to being who I was.

¡°The last couple of years were, I think, maybe uncharacteristic of what I was in the years prior to that, from not only the kind of competitive standpoint on the mound but also a health standpoint. I pride myself on being healthy and kind of being a guy that can be relied upon in a bullpen. So it's really just getting back to that and kind of back to who I was.¡±