Since 2006 - his first full big league season - Maholm has averaged 183.7 IP per season, which ranks 22nd of all pitchers that pitched between 2006 and 2011. While he has displayed great durability in the past, his 2011 season was cut short as a result of a shoulder strain. Fortunately, it doesn't seem like it was much as he was cleared for workouts on October 24th. Maholm's ability to stay on the field will be a breath of fresh air for a Cubs team that had a variety of injuries plague it's rotation last year.
Let's take a look at what Maholm has produced in the past, and what he could produce moving forward.
Over the course of the past six years, (not including the 41.1 innings that he pitched in 2005), Maholm has posted a wide range of pitching lines. His line has been as bad as a 4.76 ERA/4.81 FIP/4.59 xFIP, (his first season), and as good as a 3.66 ERA/3.78 FIP/4.03 xFIP, (his 2011 season). Below is a chart with Maholm's career numbers.
In general, Maholm has been improving - aside from 2010, Maholm's FIP has been decreasing year-by-year. Unfortunately, some of this decrease may be a result of his below average HR/FB rates over the past few years. If you take a look at his xFIP, (the same as FIP excepts it uses the league average HR/FB rate instead of the pitcher's HR/FB rate), you'll see much more varied results.
That said, let's look at something Maholm is clearly good at: inducing ground balls. Since being called up to the majors, Maholm has shown a knack for getting ground balls. Below are his ground ball rates by season:
At his best, Maholm induced ground balls at a rate that would put him in the 90th percentile amongst all pitchers. While his ground ball rate has been trending slightly down for the past couple of years, it is still well above average, and ranked close to the 80th percentile amongst all pitchers in 2011.
On the other hand, I do have a couple of concerns with some of Maholm's peripherals. His SwStr% has fallen every year since his career high of 8.4% in 2008; it stood at 5.7% in 2011, (well below the 8.6% league average). Given his declining SwStr%, Maholm's Contact% has increased since 2008, rising to a career-high 86.9%, (well above the 80.7% league average). Furthermore, Maholm has had a history of high HR/FB rates. He posted three straight seasons with a HR/FB rate above 12.0%. Fortunately, in the three years since 2008, Maholm's HR/FB rates have hovered around 7.5%, (well below league average, which was 9.5% in 2010). While some of this may have been a result of luck, Maholm did change his pitch selection after 2008. He cut back on throwing his fastball in 2009 - throwing it 8.1% less than he did in 2008 - and instead chose to throw his CB% (15.9% in 2008 | 17.7% in 2009) and CH% (10.1% in 2008 | 16.2% in 2009) more frequently in 2009. This change in pitch selection as an explanation for the decreased HR/FB rates is somewhat reassuring.
Maholm's ability to induce ground balls is his most valuable skill. If he can continue to keep his GB% high, Maholm can continue to be a league average starter, (his career FIP- of 100 is the definition of league average).
At $4.75 million for one year with a club option for $6.5 million in 2013, Maholm comes at a bargain. He has averaged 2.1 WAR per year over his career, and 2.5 WAR per year over the past four years. At 2.5 WAR, Maholm has, on average, been worth anywhere between $10 and $12 million dollars a year. Maholm could conceivably be worth his entire contract, (assuming the club option is picked up) in one year.
While Maholm isn't necessarily the young pitcher that you'd expect a team to build around, signing Maholm opens up a few different possibilities:
1. Maholm could fill a spot in the rotation left by a Garza trade.
2. Maholm could fill a void left by Garza or Dempster in 2013.
3. Maholm could be traded this July, or next off-season, and net a prospect or two.*
4. Maholm could become a long-term fixture at the back-end of the rotation.
Maholm's another asset in the cupboard, and at the cost that he comes at, is another shrewd move by TheoJed that opens up a bunch of possibilities.
* It might not be in our best interest to consider trading a bunch of the free agents that we have signed, (this matters more with a pitcher like Maholm or a player like DeJesus as opposed to someone like Sonnanstine or Corpas), for the following reason: if we sign people to major league contracts with the intention of flipping them at the deadline, or in the middle of their deal, free agents may be wary of signing with us in the future and may end up choosing a different team to sign with because they're scared that they'll just be another asset that we leverage in a trade. I'm not sure how important this effect is - it might be the case that certain players don't mind being traded - but I think it's something worth mentioning.