Jason Marquis had to grind his way through his start yesterday, not feeling quite as sharp as usual, largely because he was pitching on six days of rest. At no point in the game did he have to adapt more than when, in the Fifth inning, with Neil Walker batting and Lyle Overbay on first after a single, Marquis wound up and tripped.

On the first pitch he threw to Walker, Marquis unfurled a pitch utterly unique to his career. He had wanted to throw a changeup, but what came out of his hand looked like a curveball, or a Wiffle ball pitch thrown in the backyard. Walker, perhaps astonished, watched the 55-mile-per-hour dropball nestle into Ivan Rodriguez’s mitt. Strike one, looking.

It was the slowest pitch of the Nationals’ season, which is saying something when the staff includes Livan Hernandez and his low-60s curveballs.

“That was the plan,” Marquis deadpanned. “I’m trying to top – well, not top – go below Livo’s slowest pitch of the year.”

As Marquis slipped while pushing off the rubber, he realized if he didn’t throw the ball, he would be called for a balk and Overbay would be given second base.

“The whole thought process was just throw the ball,” Marquis said. “Because I know if it crosses home plate, whether it’s on the ground or in the air, it counts as a pitch. I didn’t want the runner to advance.”

He didn’t realize, of course, how effective it would be. “Maybe I’ll try to work on that,” he said. “No, I was just trying to get it there more than anything and do it without injuring myself.”

As a side note, Marquis offered some good insight as to why Hernandez’s slow curve works so well. Even though it looks like Hernandez just flips the ball up there, Marquis said it still, somehow, has late, sharp break. Hernandez’s 65-mph curves may look loopy, but at the last minute the action is quite sharp.

“I have no idea how he does it,” Marquis said.

FROM THE POST

The Nationals got back to .500 with a 6-3 win over the Pirates, the biggest blow coming from Michael Morse’s first homer of the season.

NATS MINOR LEAGUES

Scranton/Wilkes-Barre 3, Syracuse 2: Yunesky Maya allowed three runs in seven innings on three hits and no walks, striking out nine. Cole Kimball struck out two in one perfect inning. He hasn’t allowed a run in 7 1/3 innings this season. Jesus Flores and Roger Bernadina each went 1 for 4 with a double.

Harrisburg was off.

Salem 11, Potomac 4: Destin Hood went 0 for 2 with two walks. Jose Lozada went 2 for 4. Josh Smoker retired all four batters he faced.

Hagerstown was off.