The Arizona Diamondbacks will get compensation if they¡¯re unable to re-sign free agent Christian Walker after extending a qualifying offer to the first baseman at the start of this offseason.

A team can extend a QO to any of its impending free agents who have never received a qualifying offer before, as long as that player was on the team¡¯s roster for the entire season.

• The players who did (and didn't) receive qualifying offers

The amount of the QO, which this year is $21.05 million, is determined by the average salaries of the 125 highest-paid players in the Major Leagues.

Extending the QO guarantees the Diamondbacks will receive Draft pick compensation should Walker sign elsewhere. It's also possible that Walker could accept the offer, but that seems unlikely given the expected demand for him on the free-agent market.

• Full guide to offseason dates, rules, terms

Walker and the Mets¡¯ Pete Alonso, who was also extended a QO, are the top first basemen on the market.

Walker has until 2 p.m. MST on Nov. 19 to either accept or reject the offer.

• History of qualifying-offer decisions

This would be Walker's first taste of free agency after having to wait years to get his first shot at a big league starting job.

Selected by Baltimore in the fourth round of the 2012 Draft out of the University of South Carolina, Walker worked his way up the Baltimore system relatively quickly and was called up to the big leagues in mid-September in 2014.

The Orioles, though, had Chris Davis established at first base at the time, so there was not much of an opportunity for Walker, who was designated for assignment during Spring Training in 2017.

Walker was claimed off waivers four days later by the Atlanta Braves. The only problem was the Braves had Freddie Freeman at first, so they put Walker on waivers 10 days later to try to send him to the Minor Leagues.

Instead, Walker was claimed by the Reds, who had a guy by the name of Joey Votto playing first base for them.

So 22 days later, when the Reds tried to send him to the Minors, he was claimed by the D-backs, who had Paul Goldschmidt at first base.

It was, to say the least, a tough stretch for Walker. He was 26 at the time, with only 31 big league plate appearances to his name.

The D-backs traded Goldschmidt prior to the 2019 season, which opened the door for Walker -- and he took full advantage.

Not regarded as a good defender coming up in the Minor Leagues, Walker turned himself into an elite first baseman, as evidenced by his current run of three straight Rawlings Gold Glove Awards.

In 2024, Walker's 13 outs above average were the most by a National League first baseman, easily outdistancing the Phillies¡¯ Bryce Harper, who finished with eight OAA.

¡°I think he's incredible over there,¡± veteran shortstop Kevin Newman said of Walker earlier this year. ¡°I think that the value he brings [gives] us the confidence that all we need to do is get the ball close to him and there's a really good chance that he's gonna pick you up. It's something that doesn't really get as noticed by fans, but it does in the clubhouse.¡±

Offensively, Walker became a mainstay in the middle of Arizona's lineup, compiling OPS+ numbers of 125, 122 and 121 from 2022-24. His 146 home runs rank fourth on the club's all-time list, behind Luis Gonzalez (224), Goldschmidt (209) and Steve Finley (153).

"He's a phenomenal player," Arizona GM Mike Hazen said. "He's the best defensive first baseman in baseball, and he's a self-made player in a lot of ways. I respect that immensely, and I think what that meant to our clubhouse was a lead-by-example thing that was pretty unique."