Zach Sanders kicked off my (first) Baby Week with a guest post about Angel Pagan, and is back to close it out with another great one on the suddenly underrated Dan Haren.

With the trade deadline approaching, many names are being thrown about as teams look to improve their team now, or in the future. One of the names rumored to be dealt at this year’s trading deadline is Dan Haren, one of the best starters in all of baseball.

Haren has two years and $25.5 million left on his contract, as well as a $15.5 million club option in 2013. Because he’s not just a rental, Haren is an even more valuable commodity, and the Diamondbacks are going to make teams pay for it. Rumor has it that the club is asking for two starters and bullpen help in return for their ace.

You may be asking yourself, “Why would teams give up that much for a guy who is 7-8 with an ERA over 4.00?” Don’t let his ERA and Win/Loss record fool you, Dan Haren is a bona fide ace. Haren has thrown at least 215 innings every year since 2005, and came within two outs of reaching the 230 IP mark last year. In that time span (2005-present), Haren has been worth over 28 Wins for the Diamondbacks, as well as being the 6th most valuable pitcher in baseball over the past three seasons. Oh, and don’t forget that he has a K/BB rate of 4.93 and a 3.42 xFIP this year. Yeah, that too.

Some teams inquiring on Haren may be worried about his first and second half splits from last year. But, they should fear not, because Haren didn’t really have much of a split last year, even though that might be how you remember it. I present to you, the reader, Haren’s monthly splits from the 2009 season:

April: 2.72 xFIP (1.54 ERA)
May: 3.12 xFIP (3.50 ERA)
June: 2.81 xFIP (1.64 ERA)
July: 3.22 xFIP (2.18 ERA)
Aug: 3.64 xFIP (4.95 ERA)
Sept: 2.96 xFIP (4.79 ERA)

Haren never had a month with a walk rate above 2.00 per nine innings, nor did he have a month where he struck out less than 7.5 batters every nine innings. While he gave up a ton of homers in August (8 in 40 IP), it shouldn’t come as much of a surprise due to the weather in Arizona.

Paying for two (possibly three) and a half years of Haren is like moving out of an apartment and buying a new house. You have to spend much more money (prospects) right now , but you will be very happy with the security of knowing you have made a good investment.

Zach Sanders writes for FanGraphs. You can follow him on Twitter or reach him via This e-mail address is being protected from spambots. You need JavaScript enabled to view it .