If it's a capable middle- or back-end starter you seek, free agency presents several intriguing options this year.

But if it's a sure-shot ace you're looking for, there is only one: Zack Greinke.

This year's free-agent crop of starters can be summed up very simply as Greinke and everyone else. He's head and shoulders above the others, with a Cy Young Award in his back pocket, health on his track record, explosive stuff in his arsenal and age 29 on his bio page.

As such, Greinke will command a nine-figure deal, with five years and roughly $120 million seemingly being a popular notion.

The question is: Who will offer it to him?

Things can change frequently in the fluid world of free agency, and there is always a surprise or two, but right now the market for Greinke seems rather thin, perhaps partly because his social-anxiety disorder may take the big markets of New York and Boston out of the picture.

The Angels, who acquired him from Milwaukee in late July with the hope that he'd warm up to Southern California, will be one of his prime suitors. So will the Rangers, who missed out on Greinke at the non-waiver Trade Deadline in July and are expected to make him a priority once the Angels' exclusive negotiating window ends Friday at midnight ET.