Pete Medhurst in the radio broadcast booth at SunTrust Park in Atlanta on Wednesday. (Courtesy of the Nationals)

As a 5-year-old, Pete Medhurst would sit in front of the TV in his Harwood, Md., home with the Panasonic tape recorder his grandfather gave him and pretend he was a play-by-play announcer. On Tuesday, Medhurst, now 49, walked into the broadcast booth at Atlanta’s SunTrust Park for his big league radio debut. Nothing could have prepared the 106.7 the Fan on-air personality and longtime voice of Navy athletics for the feeling of calling his first Washington Nationals game alongside the team’s original play-by-play man, Charlie Slowes.

“My Fitbit registered 103 for my heart rate when I was doing the starting lineups and batting order and gradually went down from there,” Medhurst, whose heart was beating more normally the next morning, said in a phone interview.

Medhurst was paired with Slowes for Wednesday’s series finale in Atlanta and will be with him for the Nationals’ three-game set in Cincinnati, which begins Friday. Dave Jageler, Slowes’s broadcast partner since 2006, has moved to the MASN TV booth this week alongside analyst F.P. Santangelo while Bob Carpenter is on vacation. Medhurst will fill the same pinch-hitting role July 12 and July 14 when the Nationals visit Philadelphia.

“To know that there are thousands of people across the country that are every bit as good as I am at this or better, the fact that I’m getting this opportunity this week is just a thrill of a lifetime, especially for a guy that was born and raised in this area,” said Medhurst, who counts harness racing announcer at Rosecroft Raceway among his many regular assignments.

Slowes handled the play-by-play for the first two innings of Tuesday’s game before introducing Medhurst in the top of the third. Medhurst was tested moments later when Victor Robles lined a 1-0 pitch up the middle and Braves center fielder Ronald Acuña Jr. raced in to make a sliding catch. It wasn’t immediately clear whether Acuña made the difficult play or trapped the ball, but Medhurst nailed the call.

“I was patient enough to wait for the umpire to go up with the signal because there’s nothing worse than a guy going, ‘Safe! No, he’s out! No, he’s safe!’ " said Medhurst, whose baseball broadcasting experience includes Navy and Bowie Baysox games. “You ruin some credibility with your listeners at that point. When you fill in for Charlie or Dave, it’s one of the best radio broadcast teams in all of Major League Baseball, and fans expect the same level of performance that they get every night. That is the challenge this week to live up to that ability."

Medhurst, who settled into a rhythm after Acuña’s catch, said his nerves Tuesday compared to a time he filled in for longtime thoroughbred track announcer Dave Rodman at Laurel Park a few years ago. In the seventh inning, he was on the call for Howie Kendrick’s solo homer off Anthony Swarzak, which turned out to be the winning run in Washington’s 5-4 victory.

“Hammered toward right-center field and deep, Markakis and Acuña will watch it go, into the right-center field bleachers for a home run," Medhurst said smoothly.

“On that kind of play, you’re reading the outfielders,” Medhurst explained. “Markakis and Acuña, normally if it’s a home run they’ll just stop running, but they kept running toward the warning track where you thought maybe this will hit off the top of the wall."

Medhurst always dreamed of becoming a broadcaster, and baseball was his first love. In addition to his make-believe sessions in front of the TV, he grew up listening to Chuck Thompson and Bill O’Donnell on Baltimore Orioles broadcasts, Frank Herzog call Washington Bullets and Redskins games, and Ron Weber, the original voice of the Capitals.

“It was a free clinic every night in terms of the broadcast,” Medhurst said. “All of those guys were just ridiculously talented people.”

When Medhurst was a teenager, longtime Wizards and D.C. United broadcaster Dave Johnson gave him one of his first broadcasting opportunities, as the host of a Saturday morning high school sports show on Annapolis’s WNAV. Medhurst has called various sports for the Navy Radio Network since 1997 and has been the primary voice of Navy football since Bob Socci left to become the play-by-play announcer for the New England Patriots in 2013. He also hosts "Nats First Pitch” on Saturday mornings and the “Nats Talk Live” postgame show on Sundays on 106.7 the Fan.

Late last year, Nationals Radio Network producer Vic Ferreira told Medhurst there might be an opportunity to fill in on a future game broadcast. With the support of 106.7 the Fan program director Chris Kinard, Medhurst submitted his demo tapes. About two months ago, he learned that he would be called up to the big leagues this week.

On Tuesday night, with Medhurst’s Nationals debut in the books, Nationals PR presented him an authenticated lineup card and baseball from the game.

“My eyes welled up a little bit, to be honest with you," Medhurst said. “… The thrill and the opportunity of walking into that ballpark, it was just an extraordinary feeling to be a part of that environment.”

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