The hot stove season is always good for a few big surprises. On Friday, Zack Greinke may have provided the biggest we'll see all winter, reportedly agreeing to a six-year, $206.5 million contract with the Arizona Diamondbacks.*
While the baseball world assumed it was waiting for Greinke to decide between the Los Angeles Dodgers, his home for the last three seasons, and their arch-rivals, the San Francisco Giants,*D-Backs general manager Dave Stewart swooped in with a deal that was too good to resist. The end result is Arizona landing the top remaining player on the free agent market and one of the very best pitchers in the game.*
[Brown: Report: Zack Greinke to sign six-year deal with Arizona Diamondbacks]
In pursuing and ultimately signing Greinke, Stewart is sending a message that Arizona is ready to take a step forward in the NL West. In stealing Greinke out from under Los Angeles and San Francisco, he's shown a willingness to go toe-to-toe with his top two foes, which is not something that was anticipated. We knew they had the money and the motivation to land a top flight free-agent pitcher based on their $120 million offer to Johnny Cueto, but we didn't know they'd go to these lengths.*They were not only ready to make a play for a top free agent, they were willing and able to sign one, and now the landscape of the NL West has changed significantly.
Of course, it remains to be seen if it has changed enough for Arizona to truly contend for a division championship, but it no doubt puts both the Dodgers and Giants on their heels heading into the winter meetings. As for Arizona, this is a team that was poised for and ultimately achieved a break through in 2015, notching 79 wins and finishing third in the top-heavy division after winning 64 games in 2014. The addition of Greinke alone could push their win expectancy in the mid-80s, which puts them in the conversation.*
The Diamondbacks already have a solid core of players in place. The lineup is in a good spot with perennial MVP candidate Paul Goldschmidt providing a rock-solid anchor and A.J. Pollock looking like an All-Star caliber talent. They helped lead Arizona to the second-highest scoring offense in the NL.*If they get a better return on their investment in Yasmany Tomas and see continued progress in young players like Ender Inciarte, Jake Lamb and Nick Ahmed, their offensive ceiling may be even higher in 2016. *
The limiting factor in recent years has been pitching, and Greinke certainly provides a monster boost there. The NL Cy Young runner-up is coming off another dominant season in which he led MLB with a*1.66 ERA over 222.2 innings. It might be unfair or even unrealistic to expect another season like that, but at 32 Greinke figures to have enough fuel left to remain very effective on the front side of his deal.*
[Related: David Price says he's been saving postseason wins for the Red Sox]
Behind him in the rotation will be left-hander Patrick Corbin, who prior to undergoing Tommy John surgery in 2014 had the looks of an impact pitcher himself. Those two together and healthy for a full season give Arizona a formidable 1-2 punch that could make a difference.*

There's still a lot of offseason to go though and probably not much flexibility left for Arizona to make another splash. Meanwhile, the Dodgers and Giants likely have some new found motivation that could lead to a more aggressive approach in the weeks ahead. *To put it mildly, the next big move in the NL West will be every bit as intriguing as Greinke's decision to join Arizona. For now though, we can at least say the needle has moved, but it still has the potential to move in several different directions.*
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Mark Townsend is a writer for Big League Stew on Yahoo Sports. Have a tip? Email him at [email protected] or follow him on Twitter! Follow @Townie813