Friday was a good day for the San Francisco Giants. Not only did they down the Dodgers in extra innings on a walkoff home run, they also announced they extended first baseman Brandon Belt. While there had been plenty of rumors the Giants were attempting to lock Belt up long-term prior to the start of the season, nothing came to fruition. Given Belt just barely missed going to arbitration this past offseason and the fact extensions typically happen before the season starts, the extension was a walkoff in its own right.

As reported, the contract buys out Belt’s one remaining arbitration year after this season and extends him for four years after that. He will receive the previously agreed $6.2 million this season and then $8.8 million in 2017 and then $16 million per year from 2018 through 2021, for a total of $79 million over six years. The deal is very similar to the $75 million, six-year contract the Giants gave to shortstop Brandon Crawford this past offseason. Clearly, the Giants recognize the value of having the best homegrown infield in baseball and the savings they are getting from Joe Panik and Matt Duffy are being used to lock down the other infielders long term, but at more reasonable AAVs than signing free agents on the open market.

Belt, a fifth round draft pick, has been surrounded by expectations since he came up with the team. Belt’s minor league stats suggested he wasn’t only going to hit for high average, but he had something the Giants had trouble developing for quite some time: power. Belt struggled in his rookie season when he was fighting for playing time, but in his four seasons since, has gone on to hit .277/.352/.461. and put up 2.8, 4.2, 0.9 and 3.9 bWAR. The 0.9 outlier there is Belt’s 2014, where he was limited to 61 games.

By far, the biggest predictor of future injuries is past injuries, so seeing a player has been often injured, as Belt has been, would be cause for concern. The injuries Belt has suffered, though, have mostly been due to getting hit by pitches or in the head by knees. While having a history of concussions is always concerning going forward, these mostly aren’t injuries the Giants need to worry about impacting Belt as he ages. Really, they just need to hope that people stop hitting Belt in the head.

If Belt does stay healthy for a full season, there is still the potential for him to do even better. Belt’s line in 2015 was .280/.356/.478 and he hit a career-high 18 home runs, despite only playing in 137 games. As others have pointed out, in terms of line drive rate and ability to hit to all fields, Belt has a similar comp at his same position, Joey Votto, one of the best hitters in baseball. Belt has improved throughout his career at discerning balls from strikes and, if he continues to do so, striking out a bit less, walking a bit more and punishing more balls with the power he already has, he would be one of the best in the game. As is, he’s already one of the better first basemen in the game, even if he doesn’t improve a bit.

In terms of defense, per Fangraphs, Belt was the best defender at first in 2015 and the third best overall since his first full season and his defense has certainly contributed to his overall value. Figuring out how an individual player’s aging is going to affect his defense is no picnic, but the fact Belt will only be 33 when the contract concludes combined with the fact he plays first base makes him a good bet not to bottom out there.

Grade for Belt: C+

Assuming Belt continues to play the way he’s been playing and stays healthy, he would have been in line for a bigger payday when he hit free agency. With all of the cable television money flowing through MLB’s coffers these days and looking at the contract Freddie Freeman received, it’s hard to imagine Belt couldn’t have done better for himself. That being said, Belt had previously indicated his desire to stay in San Francisco and it’s tough to imagine him wanting leave his infield buddies behind so it looks like he took a hometown discount to stick around and shoot for another ring to add to the two he already has with the Giants’ homegrown core.

Grade for Giants: A-

The contract definitely looks like a win for the Giants. Their infield is signed through at least 2020 (the first year Joe Panik can hit free agency). Obviously, as with any signing there’s risk involved and it’s possible that Belt won’t be worth $16 million when the contract concludes, but the fact that Belt will only be 33 combined with his skillset makes this a good bet. If Belt stays healthy and keeps on doing what he’s doing, it’s already a win, but if Belt improves a bit and reaches toward his ceiling, this deal could look like an absolute steal.