The top starting pitcher on the free-agent market is heading to the desert.

Right-hander Corbin Burnes and the D-backs agreed on a six-year, $210 million contract, a source told MLB.com’s Mark Feinsand on Saturday. The contract includes an opt-out clause after the 2026 season. The D-backs have not confirmed the deal.

Burnes, who turned 30 in October, hit the market after what proved to be his only season with the Orioles, who acquired him in a trade from the Brewers last offseason. The 2021 NL Cy Young Award winner put together a strong campaign in Baltimore, finishing fifth in the AL Cy Young race and making his fourth consecutive All-Star team.

Now he joins the D-backs, who were looking to bolster what could be a championship-caliber roster. After going 84-78 in 2023 and sneaking into the postseason via Wild Card berth, Arizona made a surprising run to the World Series before losing to Texas in five games. Last season’s D-backs squad was stronger, going 89-73 but getting eliminated from the playoff picture on the final day.

Burnes by the numbers

2024: 32 GS, 194 1/3 IP, 2.92 ERA (128 ERA+), 3.55 FIP, 3.7 fWAR
Career: 199 G (138 GS), 903 2/3 IP, 3.19 ERA (129 ERA+), 3.21 FIP, 21.5 fWAR

Here is a breakdown of this move from all angles, via MLB.com experts:

Why did the D-backs make this move?
Via D-backs beat writer Steve Gilbert

Starting pitching did not appear to be an area of need for the Diamondbacks this winter with returning starters Zac Gallen, Merrill Kelly, Eduardo Rodriguez, Brandon Pfaadt, Ryne Nelson and Jordan Montgomery all under contract for 2025.

Given that surplus, the signing of Burnes sets up the Diamondbacks to move one of their other starters, which could also help with their payroll situation.

Arizona entered last season with a record-high payroll and spent somewhere in the neighborhood of $170 million. It had some money come off the books when first baseman Christian Walker and designated hitters Joc Pederson and Randal Grichuk became free agents and Madison Bumgarner's five-year, $85 million deal expired after 2024.

Injuries hampered the Diamondbacks’ starters in 2024, with Gallen, Kelly, Montgomery, Rodriguez and Nelson all missing time because of injury.

It's been no secret that Arizona had been looking to move Montgomery, who signed a one-year free-agent deal with a vesting player option for 2025. Montgomery, who was signed just after Opening Day, exercised his $22.5 million option following the 2024 regular season.

Moving the money owed to Montgomery would help offset the money that will be paid to Burnes.

Either way, adding Burnes to Arizona's rotation makes it one of the best in the game. MORE >

What do the Orioles do now?
Via Orioles beat writer Jake Rill

Who will be the Orioles' ace in 2025? For weeks, many Baltimore fans were hoping the answer to that question would still be Burnes, who was terrific in his lone season with the club.

Now that Burnes is joining the D-backs, it leaves the O's with a hole atop their rotation -- one that doesn't have an obvious solution to fill it.

Most of the top free-agent starters have signed elsewhere. The best remaining on the market include Jack Flaherty and Nick Pivetta, neither of whom is a likely target for Baltimore.

Flaherty struggled during a stint with the Orioles in the second half of 2023, while Pivetta declined a qualifying offer from the Red Sox and would cost a Draft pick to sign.

Much like last offseason -- when Baltimore acquired Burnes in a Feb. 1 deal with Milwaukee -- the O's will likely have to explore the trade market if they want an ace. Maybe they could make a move for Padres right-hander Dylan Cease or Mariners righty Luis Castillo.

If the Orioles are unsuccessful, they'll enter 2025 with a starting rotation headlined by righties Zach Eflin and Grayson Rodriguez.

Hot Stove implications
Via senior national reporter Mark Feinsand

While Burnes was the top starter available this offseason, there are still several notable arms available on the free-agent market. Roki Sasaki is the most intriguing by far, though his status as an international amateur free agent makes his situation unique. Jack Flaherty, Nick Pivetta, Justin Verlander, Max Scherzer, Andrew Heaney and Charlie Morton are among the others still on the board, leaving plenty of options for teams looking for rotation help.

• 2024-25 free agents, position by position

Diving deep
Via analyst Mike Petriello

Burnes was the best starting pitcher available, full stop, with no disrespect to Blake Snell or Max Fried. Ever since his now-legendary rebirth from an 8.82 ERA in 2019 to fire-breathing ace in 2020, he’s been one of the truly elite starters in the game, second only to Zack Wheeler in WAR, and third behind Aaron Nola and Wheeler in innings. Perhaps most importantly: Burnes has never been on the injured list with any sort of arm injury.

Which isn’t to say that red flags weren’t appearing, of course. No starter in the game is weaker at holding on runners than Burnes, and there was, over this past summer, a considerable bit of consternation about his declining strikeout rates -- from 37 percent in 2020, to 36 percent, 31 percent, 26 percent, and finally 23 percent in 2024. It’s not exactly the trend you want to carry into free agency.

Except: In September, Burnes was outstanding. After having the second-weakest strikeout rate month of his career (August’s 19 percent), he shot that all the way back up to September’s 28 percent, and it wasn’t by accident. Burnes identified flaws in his usually deadly cutter late in the season, and he brought back the sweeper that had been so dominant in 2023 yet he’d inexplicably shelved for much of 2024.

Even in a year that wasn’t always Burnes' best, his cutter (+20 run value) still rated as a top-five pitch in baseball. He’s shown the ability to mix and match six pitches as needed. He’s never had an arm problem. The deal doesn’t take him beyond age 36. What’s not to like? Arizona, which had the 10th-weakest starters in 2024, now projects as the 10th-best rotation in 2025.

Stat to know
Via MLB.com research staff

Plus-90: That is the run value accrued by Burnes’ cutter from 2020-24, easily the highest total for any pitch type thrown by any pitcher during that span. Dylan Cease’s slider ranks second, at plus-77. The next cutter on the list belongs to Guardians closer Emmanuel Clase, at plus-47. (Run value measures the impact of each pitch based on the runners on base, outs, and count.) Burnes’ cutter has been an annual standout in this regard, ever since his 2020 breakout with Milwaukee. The pitch has ranked among the top 11 in run value each season in that span, including fourth in 2020, at plus-20.