Madison Bumgarner tugged on an unfamiliar cap and pulled a No. 40 Diamondbacks jersey over his broad shoulders. For years, Bumgarner was the hardest man in the building to pin down for Giants photographers and social media staffers, but he stood there patiently Tuesday, taking photos in his new gear. When he finally got a chance to speak, Bumgarner started with some interesting words.

"Thank you guys for believing in me," Bumgarner said, with Diamondbacks GM Mike Hazen on one side and manager Torey Lovullo on the other. 

It's not hard to see why a team would believe in Bumgarner. He's the best big-game pitcher of his generation and someone who immediately brings a competitive edge to any clubhouse, but this can also be boiled down to very simple math. Sometimes there's no need to overthink things, as modern front offices so often do. Bumgarner will guarantee you 200 innings, and he has a 3.13 career ERA. Even last season, in what was considered a somewhat down walk year, he had a 3.90 ERA, 1.13 WHIP and averaged just about a strikeout per inning. 

Bumgarner is 30 years old and still a good pitcher. He is not miscast as your Opening Day starter, and there's a reason so many teams checked in when he became a free agent for the first time. All that said, it was still a surprise that the Diamondbacks were the ones to guarantee him $85 million.

Bumgarner circled the Diamondbacks from the start of the process, but he seemed to will himself there when free agency actually started to heat up. Hazen told reporters Tuesday that starting pitching wasn't his greatest need and Bumgarner was not on the front burner after an 85-win season. But the front office came around to the idea that this was too good of an opportunity to pass up. 

 

"We started to do a lot of work on [this move] and felt like the fit was too good not to pursue," Hazen said. "We knew over the next couple of years, finding somebody to anchor our rotation was going to be a need, and we felt like, this year, why not?"

Just five months after dealing Zack Greinke to the Astros, the Diamondbacks have a new ace. Hazen has proven adept at rebuilding on the fly, and a strong Diamondbacks front office put together an 85-win roster after trading Paul Goldschmidt in the offseason. 

The Diamondbacks had an MVP candidate in Ketel Marte and strong infield pieces in Nick Ahmed and Eduardo Escobar. But they still need offensive help, particularly in the outfield, and the bullpen is a work in progress. Starting pitching didn't seem to be a glaring need, with veterans Robbie Ray, Mike Leake and Merrill Kelly surrounded by talented young starters Luke Weaver, Alex Young and Zac Gallen.

But when it became clear that Bumgarner wanted to be in Phoenix, the Diamondbacks made room. The backloaded contract includes $15 million in deferred money and is structured in such a way that Arizona should be able to fill other holes over the next two months. They could turn around and trade Ray -- there are still plenty of teams seeking high-end starting pitching -- or decide to start the season with Bumgarner and Ray leading a team that's taking aim at the Dodgers. 

The Diamondbacks currently stand as the clear No. 2 in the NL West, with the Rockies stuck in a weird holding pattern, the Giants taking a clear step back and the Padres still trying to accelerate their own rebuild. But they still finished 21 games behind the Dodgers last year. 

"Madison will be a big piece for us in eliminating that deficit, but there's still a gap," Hazen said. 

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It'll be hard to catch the Dodgers, but there's another way into the dance. The Diamondbacks finished four games out of a wild-card spot last year and just so happen to now employ the pitcher who has had more success in that game than any other. That may come into play down the line. For now, the Diamondbacks are just thrilled to have a new leader. 

"He has an incredible track record, he's won world championships. To be able to put him in there every fifth day is going to be something that we're all looking forward to, especially the guys that are built around him, the 25 guys that are going to be playing beside him," Lovullo said. "Coming to the ballpark that day, I'm going to be looking forward to going to work. We're thrilled that he's here."