BOWIE—The Bowie Baysox, whose improbable second-half run gave them an unexpected place in the Eastern League playoffs, got off to a good start in their first playoff game since 2015.

Bowie, which beat out Erie for the second playoff spot in the Western Division, scored three eight-inning runs to break a 2-2 tie and beat the Harrisburg Senators, 5-3, on Wednesday night in the first game of the best-of-five series.

The Baysox play at home on Thursday night before heading to Harrisburg for the final three games, if needed.

With the Orioles off, Mychal Givens, Anthony Santander, Dillon Tate and general manager Mike Elias were on hand for the Western Division championship series.

Bowie began the season with 23 losses in its first 30 games, but finished the first half 23-15 for a 30-38 record. In the second half, the Baysox were 46-26.

“Back in April, there’s no way we thought we’d be here,” first baseman Preston Palmeiro said. “To be here now would be really awesome to put that exclamation point on the season, come back and be the Eastern League champs. Nobody could see that coming.”

Jesmuel Valentin began the eighth with a walk against Jhonatan German. He stole second and scored on Palmeiro’s triple to right. Palmeiro, the son of former Orioles first baseman Rafael Palmeiro, scored on T.J. Nichting’s sacrifice fly to center.

German had been feeding Palmeiro a diet of fastballs, but then Palmeiro pounced on a 1-2 changeup.

“It just kind of hung there and kind of floated in,” Palmeiro said. “And I was able to put a decent swing on it, and I got lucky with the outfielder diving.

“When I hit it, I thought it was going to drop for sure, but I thought he going to play it on a hop. When I hit it, I hoped Val was going to score. As soon as he dove, I was like, ‘Let’s try and get to third.’”

Cedric Mullins walked, stole second and scored on Ryan McKenna’s single to give the Baysox a 5-2 lead.

Luis Gonzalez worked a scoreless eighth for the win. Cristian Alvarado allowed a run on an RBI single by Luis Garcia in the ninth but picked up the save.

Manager Buck Britton chose Michael Baumann, who was 6-2 with a 2.31 ERA since his June promotion from High-A Frederick. Baumann no-hit Harrisburg on July 16.

Baumann retired the first seven Harrisburg batters and pitched out of trouble in the fourth when he walked Garcia and allowed a single to Dante Bichette Jr. to start the inning.

Ian Sagdal hit into a forceout, and then he struck out Nick Banks and Tres Barrera to end the inning.

Bowie scored in the first on Carlos Perez’s sacrifice fly against Kyle McGowin, who pitched in seven games for the Nationals this season.

“We had some opportunities early, and we couldn’t cash in, but we continued to battle,” Britton said. “That’s kind of been the story of the season.”

Through five, Baumann allowed just two hits and struck out six, but in the sixth he walked Cole Freeman and Garcia and gave up a single to Bichette to load the bases.

Britton removed Baumann with the bases loaded and none out for Zach Muckenhirn.

Muckenhirn allowed RBI singles to Sagdal and Barrera but eventually struck out three batters to end the inning.

“Baumann gave us a chance to win,” Britton said. “I don’t think he was as crisp as he would have liked to have been. A lot of deep counts. Drove that pitch count up.”

Yusniel Diaz’s home run to left  in the bottom of the sixth tied the score at 2.

With school back in session, the attendance was just 1,704 at Prince George’s Stadium, but that didn’t bother  Baumann.

“It’s just like any other game, but at the same time, there’s some buzz in the air,” Baumann said. “The fans are more into it. There’s more on the line. It’s win or go home.”

Shorebirds lose to Hickory: In the first game of a best-of-three series, the Hickory Crawdads beat Delmarva, 4-3, in the South Atlantic League playoffs.

Grayson Rodriguez allowed four runs in six innings to take the loss.

Adley Rutschman had an RBI double.

The Shorebirds travel home from North Carolina and face the Crawdads in Salisbury on Friday. Gray Fenter is scheduled to pitch for Delmarva.

Looking ahead: Bowie tries for a 2-0 lead on Thursday night. Tyler Herb, who was acquired from San Francisco for Mike Yastrzemski in March, pitches against Harrisburg’s Andrew Lee in Game 2.

Zac Lowther is scheduled to pitch Game 3 at Harrisburg on Friday night against Mario Sanchez.

Lowther was 13-7 with a 2.55 ERA for Bowie, and he thinks the postseason will help prepare him for the major leagues.

“It’s your job now,” Lowther said. “It’s a high-level situation so just trying to get that experience so that in the future when we’re in Baltimore, [we’ll be able to say], ‘We’ve been there, we’ve been in that situation.’ We’ve played into the middle of September before and we’re not falling flat.

“These last couple of weeks with our race with Erie, it was kind of playoff baseball from two or three weeks ago for us.”

Lowther was pleased with his season.

“I think I had a lot of ups and downs,” he said. “I’d like to go B-plus. I know I’ve got a lot more in the tank. I was really happy with my regular season, especially how I ended it. I ended very strong. I was able to start strong and end strong. I had a solid year. If I could have limited the walks, I would have loved to. I was able to compete at the Double-A level for the first time and thrive.”

Honor for Mills: In his first season as a manager, Alan Mills won the Gulf Coast League manager of the year award. Mills led Gulf Coast to a 38-15 record.

Mills spent the previous two seasons with the Orioles as bullpen coach.

He joins Britton, who last week was named the Eastern League manager of the year and Kyle Moore, Delmarva’s skipper, who was recognized as South Atlantic League manager of the year.