CINCINNATI -- Reds starting pitcher Tanner Roark faced his old team, the Nationals, for the first time on Saturday, and all he got was a lousy T-shirt.

Actually, the shirt Roark was handed by Derek Dietrich was one he was definitely proud of. It was Dietrich’s custom “Let It Fly” shirts, and a Reds teammate only gets one from him when he clears the fences. Roark did that for the first time in his career.

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“Welcome to the club,” Dietrich said as he walked by and dropped off the prize.

Roark had Cincinnati’s only RBIs but gave up two homers to Washington during a 5-2 loss before 27,748 fans at Great American Ball Park. The Nationals traded Roark to the Reds in December for reliever Tanner Rainey, who earned his first big league win after starter Erick Fedde lasted only four-plus innings. Roark has already helped a once-struggling Reds rotation have an extraordinary turnaround this season to have the second-best ERA in the National League.

Against the Nationals, Roark finished with four earned runs, six hits and one walk allowed over six innings with six strikeouts.

"It wasn't as emotional as I thought it was going to be,” said Roark, who is 4-4 with a 3.47 in 12 starts. “I was nervous before the game, but overall I felt under control. It was definitely weird facing them. It was almost like a Spring Training game, where you see these guys in live BP, facing your friends.”

After a smooth 1-2-3 top of the first inning, Roark’s day ultimately turned in the second when Gerardo Parra hit a 1-2 inside fastball to right field for a three-run homer.

"I thought I made a good pitch up and in. I checked it,” Roark said. “It was a good pitch, but that's also his hot zone. I have to know that coming in. I felt like I had had success pitching up there lately, pitching inside. He was maybe thinking along with me.”

Matt Adams’ solo drive over the center-field fence in the top of the fourth made it a 4-1 game. Roark has now surrendered only six homers this season, but had six straight starts without allowing one, with the last coming on April 17 at Los Angeles.

"I knew it was pretty good. I knew I hadn't given up in a long time,” Roark said. “At least they were bombs, that's all I care about."

Cincinnati’s offense has been resurgent of late, but stepped on itself often on Saturday. Three blossoming rallies were squashed by three balls grounded into double plays, two by Jesse Winker. The lineup was 0-for-9 with runners in scoring position with nine left on base.

Roark wound up helping himself with the bat. Runners were on the corners in the bottom of the second inning when he dropped a safety squeeze sacrifice bunt that scored Jose Iglesias. With one out in the fourth inning, Roark slugged Fedde’s first pitch to center field for a solo homer.

“That was the perfect bunt he made and the right direction, right where you want to put it in that situation. Tanner can swing the bat. He’s shown that,” Reds manager David Bell said. “He’s come up with some hits. I’m surprised that was his first career homer, just the way he swings the bat. There will be more to come.”

Roark didn’t remember trying to coax the ball over the wall as he ran to first base. But once it cleared by just enough, he played it cool against his old teammates.

"I wasn't trying to make eye contact with anybody rounding the bases,” Roark said. “I saw out of the corner of my eye [Anthony] Rendon, a little bit looking the other way. I don't know if he had that smile on his face just because that's how he is. I don't know, it was cool. It felt good."

And now, Roark’s wardrobe has expanded by one red Dietrich T-shirt.

"I'm honored to be welcomed in,” Roark said. “He's got 17 taters. First of my career, which is cool. I would have loved to win the game."