On Wednesday, the former teammates will square off on the mound, with each looking to give his club the advantage in the third of the four-game set between Houston and San Diego at Minute Maid Park.
"It will be neat to go against someone you kind of grew up with, and it will always be fun," Harrell said. "Hopefully, I can get a base hit and some bragging rights. I don't want to give one up to him, though."
That could be a difficult task, as Richard had two hits and three RBIs at the plate in his last start.
Harrell does enter his start against the Padres with some momentum. The rookie right-hander, who's tied for the team lead with six wins, allowed just one run over seven innings in his last outing against Cleveland, taking a hard-luck loss.
But Richard has been performing even better in recent games. The left-hander has won his last three outings, posting a 1.69 ERA over 21 1/3 innings in that span.
It seems the key to Richard's success is control -- in his last two starts, Richard has thrown his two highest strike totals of the season, with 79 strikes in his last outing and 71 in the start before that.
Other than that, though, Richard didn't say he had made any particular changes that could explain his improved pitching.
"I mean, it's just luck," Richard said. "Just been throwing well, getting ahead of hitters in the last few starts. That's the key to anybody pitching."
Padres: Headley expected to return
After receiving a rare day off from manager Bud Black on Tuesday, third baseman Chase Headley will return to the team's lineup on Wednesday. Headley had started 72 of San Diego's first 74 games.
The 28-year-old did appear in Tuesday's game, replacing first baseman Mark Kotsay in the seventh inning. Headley went 1-for-2 with two RBIs.
First baseman Yonder Alonso, who's been out for several games with a sore knee, pinch-hit in the ninth inning on Tuesday, a sign that he also could return to the Padres' lineup on Wednesday.
Reliever Nick Vincent was recalled from Double-A San Antonio on Tuesday. It's Vincent's second stint with the Padres, though he didn't appear in a game the last time he was with the big league club. The right-hander has gotten better results in the Minors recently after deciding to pitch exclusively from the stretch.
Fellow reliever Brad Boxberger was optioned to Triple-A Tucson to make room for Vincent.
Astros: Several moves made in outfield
Houston made four separate roster moves involving outfielders on Tuesday. Justin Maxwell was placed on the 15-day disabled list with loose bodies in his left ankle, and Scott Moore was called up from Triple-A Oklahoma City to replace him.
The Astros also reinstated Fernando Martinez from the 15-day DL and optioned him to Oklahoma City, where he had been rehabbing from his concussion. Veteran Travis Buck was designated for assignment.
Right-hander Jordan Lyles continued the team's recent run of solid starts with his one-run outing on Tuesday. Over the last eight games, Astros starters have allowed just 16 earned runs, good for a 2.36 ERA.
Astros reliever Wilton Lopez was scheduled to throw a bullpen on Wednesday. The right-hander has been on the DL since June 11 with a sprained elbow.
The Padres had won four straight over Houston until on Tuesday.
San Diego outfielder Chris Denorfia, who didn't play on Tuesday, currently has a 12-game hitting streak. It's the longest of his career, as well as the longest for the Padres this season.