HOUSTON -- The AL West race changed Sunday.

And we aren't talking about the fact that Seattle, not the Houston Astros, is now the closest team to the Rangers.

No, on Sunday, the biggest change for the first-place Rangers was this: They have a bigger, badder Yu Darvish. A comfortable, confident, efficient and even, at times, demonstrably emotional Darvish. After seven dominant shutout innings against the Astros in a game the Rangers kicked around late before winning 5-3 in 11 innings, one blunt question remained to be asked: Is Darvish back to 2013 pre-Tommy John surgery form?

Darvish answered just as bluntly: "I feel like I pitched better than in 2013."

Just for context, Darvish was the Cy Young Award runner-up in 2013.

OK, some quick details about the game. The bullpen blew a three-run lead over the eighth and ninth, which is why Darvish ended up with no decision. The Rangers offense stumbled all over the place with runners in scoring position late before Ian Desmond and Rougned Odor delivered run-scoring hits in the 11th. Matt Bush pitched two innings to get the win. All of that was nice.

Long-term, though, it was all about Darvish. This is indeed a significant development for the Rangers. Thanks to a seven-game lead, they may be able to win the AL West even without a very deep rotation, but if they want to go deep into the playoffs, they need a 1-2 punch at the top of the rotation. Darvish, now a full believer in the abilities of his two- and four-seam fastball, is ready to punch alongside Cole Hamels.

In the past, Darvish has often relied too heavily on his slider, which is a devastating pitch, but is more of a swing-and-miss pitch for when he's ahead in the count. Early in the count, batters tend to lay off it.

Just before he had the surgery in 2015, he proclaimed that he would come back more willing to throw his fastball, and he's worked hard on that this year. He entered the game throwing the fastball 54.8 percent of the time compared with 46 percent through his first three seasons. On Sunday, he threw it 54 times in 93 pitches (58.1 percent). He ended up with eight strikeouts and no walks. It was a breakthrough kind of performance.

What's more: He showed he could get swings and misses with it, too. He got 11 swings and misses on fastballs.

Afterward, the fastball was what he really wanted to talk about.

"This was my best start [since coming back]," he said through an interpreter. "I was throwing my four-seamer and sinker, and they were working really well. I didn't have to throw my slider that much. I feel like the big part of my success was the fastball. It worked well for me. I was able to use my other pitches but didn't really have to use them as much as possible. I was really able to just be aggressive."

Darvish's secondary stuff is so good and so varied that even mixing in a handful of other stuff makes him effective. It keeps hitters off balance. He also used the two fastballs as, well, more than two different pitches, ranging from 90 mph on the two-seamer up to 98 on the four-seamer.

"It was a tremendous job," manager Jeff Banister said. "The velocity variance on the fastball was impressive. He was able to use all of his pitches. I think it's a fair assessment to say these last two starts [represent turning a corner]. It's a step forward in confidence and feel for his pitches."

In the sixth and seventh innings, as he pushed to his longest post-op outing, he was able to mix in the secondary stuff to create unpredictable patterns when he got in trouble. He got the final out of the sixth on a curve to Carlos Correa, who swung over the top of the ball and grounded to third. He got the final three outs in the seventh on seven pitches after a leadoff single. He used four types of pitches in that sequence.

"He did a really good job," said new catcher Jonathan Lucroy, who caught Darvish in his last start as well. "The first time we just had to feel each other out. It was kind of getting to know him and what he likes. Today, he shook off a couple of times and shook to really good pitches. He knew what he wanted to throw. He saw stuff, and he acted on it. That's a beautiful thing."

What the Rangers are seeing is the Darvish they've always dreamed of: a power pitcher first with an unfair assortment of secondary pitches.

It's the kind of pitcher who carries a team deep into October.

Twitter: @Evan_P_Grant