What can we expect from Joel Hanrahan?

Acquired from the Pirates the day after Christmas, Joel Hanrahan comes to the Red Sox with something to prove. Although Hanrahan didn't cost the Sox much big league talent (an underrated Mark Melancon and medium-upside Jerry Sands), he will immediately take over for Andrew Bailey as the team's closer.

Hanrahan was a very effective reliever during his three seasons in Pittsburgh. In 2010 he had a 3.62 ERA with 100 strikeouts in 69.2 innings. He took over as their closer in 2011, saving 40 games with an impressive 1.83 ERA. Hanrahan had a great start to the 2012 season -- and finished the year with a 2.72 ERA -- but saw his ERA in July, August, and September climb from 2.38 to 2.89 to 5.00. Any team should be happy with 36 saves and a 2.72 ERA, but there are some red flags in Hanrahan's 2012 season that should cause some concern.

When looking at pitching statistics, especially with a reliever with fewer innings, it is important to consider the luck and timeliness involved. FIP (Fielding Independent Pitching) measures a player's ERA, assuming that performance on balls in play and timing were league average (i.e. take out the luck). Hanrahan's 2010 FIP was 2.62, his 2011 FIP was 2.18, but his 2012 FIP was 4.45. His 2012 FIP was much higher than his 2012 ERA for two reasons. One, his BABIP (batting average on balls in play) was only .225 (compared to the league's average of .293), suggesting that when batters made contact, Hanrahan was fortunate enough to have them find a defender more than the average pitcher. Hanrahan also stranded an insanely high 89.7% batters on base. So, when a batter did reach base, he was lucky enough to leave that runner on base nearly 90% of the time (the league average last year was 72.5%).

We now know that Hanrahan was lucky last year, but why did he seem to take a step back? The answer is his inability to throw strikes. His walks spiked last year to 5.43 per nine innings; this is well over the league average 3.05 BB/9, and almost twice as high as his 2.73 BB/9 the previous two seasons. Of even greater concern, Hanrahan's walk trouble came near the end of the season -- he issued 10 walks in only 9 September innings last year. If this trend continues, fans will be frustrated this season with a closer who jeopardizes wins by allowing free passes. Fortunately, Hanrahan's former manager offered some solace to Red Sox fans:
"We couldn’t get save opportunities for him. That complicated things for his mindset and routine. He did everything he could to stay ready. We tried to keep him on some kind of rotation and use him every third day when we could. But we couldn’t get the ball to him in the ninth inning with a lead. He’s a guy who needs to throw to stay on line and stay sharp,” Hurdle said Thursday."

So according to Hurdle, as long as Hanrahan is receiving consistent save opportunities, we should not see the wild reliever that showed up last year. Considering how strong the bullpen looks this year, Hanrahan could be in line for 40+ save opportunities. Let's just hope he is mentally prepared to pitch to the pressures of Boston fans and media, which are slightly more demanding than in Pittsburgh.

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