There has been very little to complain about in regards to the Pittsburgh Pirates rotation. The group is currently tied for the third best WAR in baseball, along with the third best ERA and the fifth best xFIP. There has been one trend which is a bit of a concern, and that has been the issue of stolen bases. Ken Rosenthal pointed out the problem today, drawing the connection to new catcher Francisco Cervelli.
#Pirates, post-Martin, have allowed MLB-high 26 SBs. Rank 18th in CS percentage; 7th last season. Also last in walk rate; 6th last season.
— Ken Rosenthal (@Ken_Rosenthal) April 29, 2015
The walk rate is a different subject, but in terms of the stolen bases, I don’t think this can be placed on Cervelli. A closer look at the Pirates’ starters will show that the stolen bases are coming off specific pitchers, with two in particular being a problem. Here are the opposing stolen base numbers against Pirates starters.
A.J. Burnett – 7-for-7
Francisco Liriano – 3-for-4
Jeff Locke – 3-for-6
Gerrit Cole – 2-for-2
Vance Worley – 1-for-1
Only Locke has a good caught stealing rate, falling far below the 70% range or better that would make stolen bases worthwhile. To get an idea of how frequently runners are stealing, lets look at the percentages of stolen base attempts, divided by opportunities where a runner was on base with second or third base open.
Burnett – 17.9%
Liriano – 12.1%
Locke – 17.6%
Cole – 6.7%
Worley – 2.8%
The NL average is 6.2%, which means that opponents are running on Burnett, Liriano, and Locke far more than average. Once again, the numbers against Locke (in a small sample size) aren’t bad, so it’s not a problem that runners are going at will. It is a problem that runners are stealing against Burnett almost three times as often as the average pitcher, and all of them have been successful. Although I don’t know how much of an issue that has been, since Burnett has a 1.80 ERA and a 3.50 xFIP.
A few people responding to Rosenthal also brought up the fact that the Pirates went up against Billy Hamilton and the Reds for their first three games. In that series, Hamilton stole six bases, and wasn’t caught once. He accounted for both of Gerrit Cole’s stolen bases and stolen base attempts, and added two for Burnett. If you remove the Hamilton factor, the results are still the same, with runners stealing at an increased rate off Burnett, Liriano, and Locke, and being very effective against the top two guys.
Cervelli’s caught stealing rate is down, with his 19% rate being his lowest in the last three years. The amount of opportunities is way up this year. He’s seen 26 stolen base attempts in 139.2 innings this year. He had 24 in 348 innings last year, and 28 in 316 innings in 2011. The rate at which opponents are stealing is way up this year. There might be some better results if Martin was the catcher, but the biggest factor here seems to be the pitching staff, specifically Burnett and Liriano.