According to Nick Cafardo of the Boston Globe, the Boston Red Sox have been scouting Phillies lefthander Cole Hamels, with possible intent of constructing a deal to acquire him.

“Hamels is Philly’s most tradeable commodity. They would have to score huge to make a deal. The Phillies have been scouting Boston heavily all season. At one point they had their top people at seven of eight Sox series. And now the Phillies are scouting Boston’s farm system.” -Nick Cafardo, Boston Globe

Cole Hamels is one of the best left-handed pitchers in the game. The 30-year-old holds a 2.93 ERA on the year, with 106 strikeouts and a 2.6 WAR. Hamels current contract has four-years remaining at around $90 million. That’s a big chunk of change, but it’s the price you play for a top-of-the-rotation pitcher.

No one here is doubting Hamels’ talent, and I’m sure there’s plenty of teams around the league that would love to add him to their rotation. While Boston may be one, it might make more sense not to pursue a deal with Philadelphia.

I’m not going to complain about his contract. $22.5 million per year isn’t awful for a player of his caliber. One of the main problems I see is what the Red Sox would have to give up in terms of players and prospects. If you want a deal to compare this to, look at what Oakland gave up for Jeff Samardzija. Addison Russell was the prospect they parted ways with to acquire Jeff (and Jason Hammel, but Samardzija was clearly the real prize). Russell, 20, is listed as the fifth best prospect in all of Major League Baseball by Baseball America. Chicago must have been jumping for joy when they landed him in the deal.

Philadelphia will be looking to do the same.

The only problem is, Boston doesn’t have one prospect in the top-five. They do, however, have Blake Swihart (14) and Henry Owens (15). Given what Chicago got for Samardzija (who is a good pitcher, but not as good as Hamels in my opinion) the Phillies will want at least one of Swihart and Owens, if not both.

While trading unproven talent for someone who you know can succeed at the Major League level is sometimes a smart move, Boston has proven to be one of the best in the league at developing home grown talent into stars and quality players. The potential shown in both Owens and Swihart is incredible, and Boston could have some serious gems in them. While Hamels would be the type of guy that could help them contend next year, Swihart and Owens (or whoever would be in the trade) could prove to be even more valuable a few years down the line.

Aside from the idea of parting with top tier prospects, there’s another thing standing in the way; Boston is already trying to acquire an elite lefty, except this ones already here. That’s right, the ongoing contract negotiations between Jon Lester and the Red Sox.

While having a one-two punch of Jon Lester and Cole Hamels would be incredible, it’s a little unnecessary. Let’s say Lester is re-signed for $130 million. Bringing in another pitcher making $20 million or more per season (like Hamels) would mean devoting a ton of your salary to pitching.

Now say Lester walks in free agency, and Boston traded for Hamels. Boston essentially just traded a few elite prospects to get another pitcher of Lester’s caliber back, when you could have had both if they just gave Lester a deal. Keeping Jon and choosing to either A) Keep the prospects and develop them into the next wave of young talent or B) trade them for a bigger need (middle of the order power bat).

Comparing Lester and Hamels as to decide which one a team would rather have is almost a waste of time. Both players have impressive ERA’s for their career (Hamels’ is 3.35, Lester’s is 3.66) and both have WAR ratings in the 30’s. They’re each 30-year-old left-handers, so what’s the deciding factor here?

Lester has proven to be a great option in Boston. Some players (see: Carl Crawford) simply can’t handle Boston for whatever reason it is. Lester has proved that he can indeed handle the pressure in playing in a city like Boston. Now take just Boston out of the equation, and just look at the American League. Hamels has pitched in the National League his entire career. Who knows if he could flawlessly make the change from NL to AL? If the Red Sox are going to be giving up top-of-the-line prospects for him, the risk is simply too large when you could just re-sign the proven ace, Jon Lester.

The only reason a trade for Hamels would be justified is if Boston is 100% certain that they won’t be able to lock Jon Lester up on a long-term deal. Then acquiring an ace like Hamels does make sense. But if not, the team may be best suited to step away from the situation, and move on to something else.