SAN DIEGO -- Just as quickly as Harold Ramírez arrived at the Nationals' clubhouse at Petco Park on Monday afternoon, he was introducing himself and shaking hands with his new teammates.

With a massive smile, the 29-year-old made the rounds before even changing into his pregame gear.

“I really feel very excited to be here in the big leagues, to be here with the Nationals,” Ramírez said. “I just really want to give my 100 percent and take advantage of this opportunity.”

After flying cross country, Ramírez pinch-hit against the Padres on Monday and Tuesday. In Wednesday’s 8-5 loss, he was in the starting lineup, batting sixth as the designated hitter. Ramírez was 1-for-4 with an RBI single.

“He loves swinging the bat,” manager Dave Martinez said. “He’s a good teammate, I’ve seen him talking to everybody and stuff. So he’s been good. We’ll get him some at-bats and hopefully get him going. I know he can drive the ball -- he hit a ball really well to right field today. We’re going to need him.”

Ramírez joins the Nationals as his fourth Major League club. He was designated for assignment by the Rays on June 7. Eight days later, the Nats signed him to a Minor League contract. They wanted him to get back into the swing of game action, and he appeared in seven games with the Triple-A Red Wings (hitting .375) before getting the call for the Padres series.

“He DH’d, he played some first with Tampa,” Martinez said. “We’re going to get him some work out in left field as well, or anywhere in the outfield, and then we’ll go from there. But we definitely love his bat.”

A season after posting power numbers with the Rays -- including career highs in hits, homers, RBIs, runs, walks, stolen bases, batting average, on-base percentage, slugging percentage and OPS -- Ramírez’s offensive production dipped from his .313 batting average. In his first 48 games this year, he batted .268 with one home run.

“Like I did before, I got to take advantage of every at-bat I have,” Ramírez said. “I just got to have a good approach.”

In a Nationals lineup with lefty-hitting outfielders Eddie Rosario and Jesse Winker, Ramírez adds a valuable matchup as a righty. Since 2020, Ramírez ranks first among all players with a .337 batting average against southpaws.

“I expect him to do what he did last year in Tampa,” Martinez said. “He had a really good year last year. He’s a really good hitter. … We could use that bat, and we definitely could use him against left-handed pitching.”

The series in San Diego provided a snapshot into how Ramírez could be utilized in the Nationals' lineup. On Monday, he pinch-hit for Rosario in the seventh inning, facing lefty Adrian Morejon. The next day, he pinch-hit for Rosario again in the sixth frame against southpaw Wandy Peralta. Ramírez stayed in the game to record his first double as a member of the Nats off righty Jeremiah Estrada in the eighth inning.

“He seemed like he was trying to take some good quality team at-bats,” right fielder Lane Thomas said. “He got a hit yesterday with the double, and I think he’s going to be a good piece for us.”

The Nationals are traveling to Tampa, Ramírez’s home park from 2022-24, for a three-game series beginning Friday. Ramírez will see his former teammates, but he already has plenty of familiar faces on the Nats. He said previously knowing Rosario, Joey Meneses, Ildemaro Vargas and Keibert Ruiz gives him instant team chemistry.

That level of comfort combined with the excitement of a fresh opportunity are only some of the reasons why Ramírez sported a smile in San Diego.

“I'm really always like that,” Ramírez said. “I just try to enjoy my life. I'm always smiling. I'm always playing around like a little kid. So that's my personality.”