Of starting lefties on the free agent market this year, Jordan Montgomery and Blake Snell are at the top. Snell, now a two-time Cy Young winner, is the marginally more expensive option who will probably entertain the more competitive chase, but the Astros would be better off pursuing Montgomery. Not only would he be less expensive than Snell, he'd be more likely to take a deal that falls under Jim Crane's preferred contract limits of five years, $150 million. Predictions for Montgomery's next salary range from five years, $127 million to six years, $150 million, both of which are numbers that could be easily modified to fall within Crane's range.
Montgomery might not be a Cy Young winner, but there's a reason he and Snell are expected to put up comparable contract numbers in free agency this year. For the Astros, there's a lot to like here: a lefty to add to a rotation with only one at the moment (Framber Valdez), a pitcher who pitched 13 more postseason innings than Justin Verlander and came out with a better ERA this year, and a star who'd be coming from a cross-state team to the other half of a rivalry that's heating up more than ever before.
Like a Yoshinobu Yamamoto contract, a Jordan Montgomery contract would easily break through the luxury tax threshold. But he's a pitcher who mixes deftly and healthily between strikeouts and pitching to contact, a lefty to add to a rotation that desperately needs one, and signing him would be a spiritual middle finger to the Rangers. He's the whole package.