The journeyman outfielder, who popped out against Antonio Bastardo to end the game, went 2-for-5 in the Nationals' 4-2 loss to the Phillies.
Hairston, who entered play Tuesday 12-for-30 (.400) with five homers, five doubles, nine RBIs and a 1.521 OPS in his career against Hamels, wasted no time continuing that trend by singling in his first at-bat.
"I expect him to not get cheated up there," manager Davey Johnson said of the Nationals' newest player. "In his career against this guy, he's hit him great, and it's a good time to welcome him to the club."
Even with his numbers against Hamels and a .307 lifetime average against the Phillies, Hairston said he does not put much stock in previous performance. When one reporter asked him about his ridiculous numbers against Hamels, Hairston replied, "ridiculous, like bad?"
"Each day is different. He might pitch me different than he's ever pitched me tonight," Hairston said. "I don't know what's going to happen. I just try to put myself where I'm in a good hitter's count and I got to see what he's working with."
The veteran outfielder did not play in the Nats' series-opening loss Monday, and he said his flight was delayed twice coming to Philadelphia. But he was welcomed when he finally arrived at the field. Washington is the sixth stop in a 10-year Major League career for Hairston, and he noted it was nice to see the familiar faces of former teammates Gio Gonzalez, Kurt Suzuki and Chad Tracy in the Nationals' clubhouse.
Hairston was brought to the Nationals to primarily come off the bench and face left-handers, according to general manager Mike Rizzo. The 33-year-old said he is comfortable in that role, and is happy to be involved in a playoff push.
"I haven't been in a winning environment in quite a while," Hairston said. "It feels good."
Stephen Pianovich is an associate reporter for MLB.com.