Kei Nishikori survived an early scare Wednesday to claim a come-from-behind victory over German Matthias Bachinger in the second round of the RBC Tennis Championships of Dallas, an ATP Challenger Tour event.

Two days after picking up his first win since returning from a five-month injury layoff, former world No. 4 Nishikori was made to work in his first meeting with his 162nd-ranked foe but eventually prevailed 4-6, 6-4, 6-4.

"It can't be helped that I can't hit aggressively because I've just returned (from injury)," Nishikori said.

"I made mistakes and my serves were poor. I was finally able to play decently in the last few games. It took time for me to gear up, but it was good I was able to end the way I did."

Nishikori broke his opponent's serve first in the third game of the first set, but Bachinger quickly returned the favor and continued to take advantage of the top seed's wayward forehand groundstrokes.

In a tense second set, Nishikori saved two break points in game eight and landed an unplayable drop shot to break back in the ninth.

With his rhythm very much discovered in the final set, Nishikori dominated the court to close out the 2-hour, 2-minute match.