So far this spring, Bryce Harper has looked strong at the plate. His plate discipline has resulted in three walks in 11 plate appearances. In batting practice, the 21-year-old has sprayed the ball all over the field. On Friday afternoon, with his surgically-repaired knee performing as well as he hoped, Harper showed off what he can do when fully healthy: hit left-handed pitching.

Harper has had some trouble with left-handers in the majors leagues. In 2012, he started off hitting left-handers well before slumping. Still, he finished the season with a .240/.300/.415 split. Last season, as his left knee plagued him  following his collision with a wall  May 13, his performance against left-handed pitchers declined and he finished with a .214/.327/.321 split against them.

But on Friday afternoon, he launched a two-run home run off Houston Astros left-hander Brett Oberholtzer. The two-seam fastball was high and in — “a really good pitch,” Harper said — but he still managed to make good contact. The ball appeared headed to the right of the foul pole right field, but the  swirling winds at Space Coast Stadium kept it fair and carried the ball over the fence for his first home run of the Grapefruit League season. “I knew I got it fairly good, but it thought it was gonna be nine feet foul,” he said.

The hit represented a lot to Harper. Last season, his lower body betrayed him.

“My knee just gave out every single time, on every single pitch on the outside half or anything,” he said. “I didn’t have the swing that I wanted to have. My knee killed me every time I swung, and this year it’s a little bit different. I can stay back and not explode on my lower half and have to go. If there’s a curveball and I’m sitting back on it, I’m ready to go, I had to go. It was that painful that I had to just go. If it was a curveball or something like that, the guy threw me one [Friday] that I check-swung on it a little bit, but I could finally do that. …  So that felt great, knowing that I can do that is really nice.”

Harper has played in four games so far this spring and said the knee has “felt great” and has had “zero pain” in it. He remains excited that he can fully use his knee. He still has treatment to maintain on it. And, he has been able to build strength back in his legs. “That’s huge,” he said.

Manager Matt Williams, too, is pleased with Harper’s swing and approach at the plate. What has impressed him more than that is the way Harper has carried himself this spring.

“What I’ve liked is his demeanor and the way he’s gone about it and that’s important,” Williams said. “If he goes about it the right way everything takes care of itself and you’ll see all those things come like we all expect. The way he has gone about his batting practice, his fielding work, his base running extra work, all that stuff is leading him right down the right path. He’s right on it right now.”