PHOENIX -- Merrill Kelly knows who he is as a pitcher. The D-backs right-hander is aware of the fact that he doesn't have a blistering fastball that he can just blow by hitters while he racks up the strikeouts.

No, for him to be successful, he wants to induce weak contact early in counts and let his defense work behind him.

Sunday afternoon was a perfect example of that as Kelly cruised through eight innings as the D-backs beat the Cubs, 6-4, to salvage the final game of the three-game series at Chase Field.

"It's a belief in the game plan, it's conviction with his pitches and then trusting the guys around him," D-backs manager Torey Lovullo said of Kelly. "He set a terrific tone for us. He's locked in right now."

The Cubs came out swinging against Kelly. They were aggressive in counts and Kelly was able to use that to his advantage, recording numerous early-count outs.

In fact, he was so efficient with his pitches that he entered the ninth inning having thrown just 75. That put him on pace to break the club record for fewest pitches in a complete game, which is 93.

When did Kelly realize that he was on such an impressive pace?

"I think it was probably the fifth," Kelly said. "I think I had like 47 pitches or something like that. I kept kind of checking. I do check throughout the game just to see where I'm at compared to where the game is at and how we're flowing. But there were a couple of times I looked up and I knew that I had a chance to get the whole thing done."

Kelly allowed four hits and two runs over the first eight innings when Lovullo decided to send him back out in the ninth for what would have been Kelly's first complete game in the big leagues. The right-hander did throw a complete game during his time pitching in Korea.

His outing lasted just two batters after that eighth inning, though, as he allowed a leadoff double to Kris Bryant and an RBI single to Javier Báez, ending his outing.

"Obviously frustrated that I couldn't finish it myself," Kelly said.

Kelly's line got further skewed as closer Joakim Soria allowed one of the runners Kelly left on base to score, tagging him with his fourth earned run.

Still, it was another outstanding outing for Kelly, who has been the team's best starter this year by far.

Sunday, everything synced up just the way he needed it to go.

"You guys have watched me, I feel like long enough, that's what I try to do," Kelly said. "I try to get quick outs, I try to be efficient. You know, I'm not the 95-98 mph guy that's going to punch everybody out. So I've got to rely on my defense a lot. I've got to rely on weak contact and getting on and off the field as quick as I can. I just think today our game plan matched up with their aggressiveness."