USS Mariner on Jason Bay:

He’s 31 years old, right-handed, and not really much an outfielder anymore. He has classic old player skills. In fact, he’s eerily reminiscent to some other free agent the M’s blew a lot of money on.

Bay, 2009: .267/.384/.537, 15% BB%, 30% K%, .269 ISO, -13.9 UZR, +3.4 wins
Sexson, 2003: .272/.379/.548, 14% BB%, 25% K%, .276 ISO, -9.6 UZR, +3.9 wins

The numbers are from Sexson’s last healthy season before the M’s signed him – you’ll recall that he missed most of his contract year with a shoulder problem, but then went right back to being the player he was before the injury. Interestingly, Sexson was actually headed into his age 29 season when the M’s signed him, so Bay’s actually even further into his decline phase than Richie was. Richie made better contact than Bay does, if you can believe that. Their power levels were similar, and they both offset the low batting averages by drawing a bunch of walks.

In terms of skillsets, they’re basically the same player – quality (but aging) power hitters who don’t fit the park and play defense like a DH. These are the types of players that make the worst free agent signings. Power is overvalued in the market, while defense is undervalued, so sluggers almost always get paid more than they’re worth. Toss in the fact that this skillset doesn’t age well, and you have a recipe for disaster.

Well put. Bay's a nice player, but he's past the phase of his career where he was an intriguing young player, and is now an increasingly scary commodity. He doesn't make contact quite as well as he used to, he doesn't play defense, and he runs gingerly. Obviously, he's still a very good player and he may have some good seasons left, but this is not the kind of player you want to pay market value for. 

A couple of points here:

1) The return for the Bay trade so far hasn't been so hot, clearly, but I hope it's clear that trading him was, at least, the right idea. Bay is now an impending free agent and might have played his last game for Boston, which failed to sign him to a long-term deal. If Boston couldn't do it, then the Pirates almost certainly couldn't have, not that they should have wanted to anyway. 

Bay is a Type A free agent, which means the Bucs would have probably received compensation picks for him, but I'm not sure Andy LaRoche and Bryan Morris aren't worth more than those comp picks anyway, and they certainly were worth more than those picks when they were acquired.

2) The case of someone like Sexson shows how small-market teams can compete even with the deck stacked against them. Since Sexson wasn't yet eligible to become a free agent, the Brewers were able to sign him before the 2001 season to a cheap four-year, $17 million deal that carried him through his age-29 season. He then signed a backloaded $50 million contract with the Mariners that quickly became a debacle because he only had two more decent seasons left in him. 

Bay just turned 31, and he's only now reaching free agency. Whoever signs him is very likely to be paying more for what he did in Pirates and Red Sox uniforms than anything he's likely to do going forward. It's obviously way too early to shut the book on Bay. Obviously. But there are lots of warning signs there, and most of the time a player's best seasons come before he's eligible for free agency.