TEMPE, Ariz. -- Daniel Nava spent the first four months of the 2015 season with a sprained left thumb, so he couldn't hold the bat with his top hand and could barely hit baseballs off a tee without pain. His left knee barked at him all summer, so he also couldn't generate much power off that leg.
Attacking right-handed pitchers from the left side of the plate -- the skill most responsible for Nava's unfathomable ascension to the Major Leagues -- was a nightmare.
"I was just hoping that I would take a good swing on a certain pitch," said Nava, who finished the season with an underwhelming .194 batting average and .245 slugging percentage for the Red Sox and Rays.
• Spring:Tickets | Ballpark | 40-man roster | NRIs
"The two components of not having a strong top hand and not having a strong back side, I guess it all collided just to make things a little more challenging than I would've liked."
For Nava, this spring isn't just about proving he's capable of semi-regular playing time as the Angels' left fielder; it's about re-learning the mechanics that once made him such a sound hitter.
The initial results have been encouraging.
In his first seven Cactus League games, Nava has accumulated 10 hits -- three of them for extra bases -- in 17 at-bats. He's walked four times and has yet to strike out. More importantly, he's working deep counts, seeing the ball deep and driving pitches to the opposite field, rekindling the three traits that once defined him.
"I feel different," Nava said. "I feel more of what I used to be."

Nava still managed a .315 on-base percentage last season, just two points below the Major League average. But he hardly got hits and he barely hit for power, because he couldn't put weight on his back side as a left-handed hitter, which kept him from driving the ball.
"So when it came time to sit back on a changeup, or to time a pitcher up, I couldn't time it up, because I had nothing to go off of, because [my left knee] was hurting," Nava said. "I was floating toward balls. I couldn't figure out, 'Why am I rolling this ball over? Why am I popping this one up?' And then rather than trust myself, I started to feel for swings to try and just do things that you shouldn't do with your swing."
The Angels are counting on Nava to be their No. 2 hitter, directly in front of Mike Trout, against right-handed starters, because putting him there prompts Kole Calhoun to bat fifth and makes their lineup look a lot deeper.
Nava's left hand had fully healed by late July, after a two-month stint on the disabled list. He got a platelet-rich plasma injection on his left knee over the offseason and reported to Spring Training fully healthy. Then he began to work with Angels hitting coaches Dave Hansen and Paul Sorrento on his trademark approach.
Nava positioned a ball on a tee directly in front of his chest, to visualize staying back, seeing pitches as they travel through the strike zone and driving them the other way.
"I just needed to feel it again, because every time I did it last year, it really hurt," Nava said. "Now, it doesn't hurt."