Taijuan Walker made his MLB debut in 2013. But as the Seattle Mariners entered the 2016 season, they were still waiting for him to arrive.

By that, we mean arrive in the big-picture sense—as in, deliver on his considerable promise and start making opposing hitters look foolish.

Six starts in…it’s happening. And it’s helping the Mariners emerge as a serious threat in the American League West.

Through 32 innings of work, the 23-year-old right-hander owns a 1.97 ERA with 29 strikeouts. Yes, he left Friday’s start against the Houston Astros after just two innings because of neck spasms.

But he said Saturday he’s feeling better and expects to take his turn Wednesday against the Tampa Bay Rays, per Ryan Divish of the Seattle Times.

That’s excellent news for the M’s, who sit atop the division at 19-13 entering play Tuesday, 1.5 games up on the Texas Rangers

Felix Hernandez remains the undisputed monarch of the Seattle rotation. But Walker is looking increasingly like a more-than-worthy No. 2 one season after posting a 4.56 ERA in 29 starts.

What’s the difference? For one, Walker is keeping the ball in the park.

In 2015, he surrendered 25 home runs in 162.9 frames. That works out to 1.33 home runs per nine innings, which was the eighth-highest total in baseball among qualified pitchers.

This season, Walker has allowed just three homers, lowering his HR/9 rate to a far less gaudy 0.84.

While the usual small-sample caveats apply, the key seems to be Walker relying less on his fastball and more on his offspeed pitches.

“Walker has been working to develop his curveball,” notes ESPN’s Mark Simon, “but while he’s doing so, his splitter (which some call a changeup) has been terrific.”

Indeed, Walker has upped the use of his changeup from 18.3 percent last year to 21.5 percent and has thrown his curveball 11.6 percent of the time compared to 7.2 percent in 2015. Use of his fastball, meanwhile, has dipped from 64.8 percent to 56.4 percent.

Concurrently, his groundball percentage has climbed from 38.6 percent to 50.5 percent.

That’s a lot of numbers, and they tell a story. But to get an idea of the leap forward Walker has taken, just watch him on the mound. There’s an unmistakable confidence—an air of control.

Skipper Scott Servais broke it down after Walker fanned 11 in a 3-2 victory over the Astros April 25, per Doug Miller and Brian McTaggart of MLB.com:

We’ve really seen that he has the ability to turn the dial up. Later in games there’s plenty in the tank. The adrenaline gets flowing, he gets a little emotional and he gets after it. He doesn’t back off. He keeps going after it and he’s got good stuff. He believes in himself and we certainly believe in him.

The Mariners should also believe in their chances to taste the postseason for the first time since 2001.

After winning 87 games and narrowly missing the playoffs in 2014, Seattle stumbled backward last season, finishing a disappointing 76-86.

Now, they’re squarely back in the mix, thanks in no small part to a starting staff that ranks second in the American League in ERA behind the Chicago White Sox.

The Rangers are a threat to repeat as division champs, particularly with Yu Darvish set to return from Tommy John surgery. And Houston—last year’s darlingis dangerous despite a disappointing start. The Los Angeles Angels and Oakland A’s are a notch below the Texas twosome, but neither is a complete pushover.

Like the rest of the Junior Circuit, the West is wide-open.

Right now, however, the Mariners might be the favorites with vintage Robinson Cano pacing the offense and Walker and Fernandez throwing like a pair of aces.

That’s exactly the role Walker could soon inhabit full time, as Jason A. Churchill of Prospect Insider outlined:

For years, many assumed Walker had ace upside because he threw hard and was athletic. I always contended he was likely a No. 2, and while I still see that for his ultimate long-term future, there’s a chance he’s not only a No. 1 in a year or less, but also an outside shot he’s among the 10-12 true aces in Major League Baseball by the time 2017 gets underway.

It’ll undoubtedly soothe some nerves in the Pacific Northwest to see Walker take his next turn and pitch well, putting the neck issue behind him.

Assuming he does, the Mariners—whom Bleacher Report’s Joel Reuter slotted at No. 3 in his most recent MLB power rankingswill have a clear course to October.

And their arrival, not coincidentally, may well coincide with Walker’s.

 

All statistics current as of Baseball-Reference.com and FanGraphs unless otherwise noted.

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