Jordan Zimmermann's slider is the key to his success.

What To Look From Jordan Zimmermann On The Mound Today

Washington Nationals starter Jordan Zimmermann, who many viewed as the ultimate steady force during last year’s tumultuous season, has been one of the team’s more inconsistent starters in 2014. Prior to his most recent start against the Philadelphia Phillies, Zimmermann had allowed fewer than four runs just once in his previous five starts, an had allowed at least seven hits in each of those appearances.

On Tuesday, however, when he took the mound against Philadelphia, he flipped the switch to the 2013 Zimmermann that had many arguing he was the staff’s best hurler. In eight innings he allowed no earned runs, just five hits, and earned the Nats a Curly W. So what changed? And what does Jordan need to do to be the hurler we saw on Tuesday, vs the Hurler we’ve seen in his previous five starts?

1. Throw Breaking Balls For Strikes

In Jordan’s most recent start, he was able to spread 102 pitches over eight innings of work. How was he able to do this? By having far better command over his breaking balls. 81% of his off-speed pitches registered as strikes against Philadelphia, where in his previous five starts he threw breaking balls as strikes only 66% of the time. By locating those pitches in the strike-zone early in the count he was able to…

2. Command More Pitcher’s Counts

An interesting note about Zimmerman’s poor starts is that while his control has been down (lower strike %), his walk totals have not gone up significantly. In fact he never walked more than two batters in the “bad” starts, and in his worst outing of the year against Arizona on 5/12, in which he surrendered 10 hits and five runs, he gave up no walks. So what gives? It appears when Zimmermann is getting into trouble with bad counts, he is relying on placing his fastball in the zone to not surrender any free passes. These fastballs are getting put into play at a much higher rate than his other pitches, which are resulting in hits, runs, and sometimes Nats’ errors.

A look at FanGraphs shows that in 2014 his fastball has produced a negative value (-2.4) for the first time since 2010.

3. Throw The Slider Effectively

Jordan threw his slider 26 times in his most recent start, which was by-far the most he had thrown the pitch in any game this season. He also threw the slider for a strike 85% of the time, which was also by far the pitch’s best performance in 2014. Looking back at 2013 and 2012 for Jordan, he threw his slider more often overall and had some pretty effective seasons. He obviously will need to both command more pitcher’s counts and throw his other breaking balls for strikes to be able to throw his slider at this high of a rate, but without the ability to use his most valuable pitch, it will be difficult for him to succeed on the mound.

Last season it seemed Jordan Zimmermann was the only thing going right for the Washington Nationals in the first half of the year. As a team with the highest of expectations, the Nats struggled out of the gate and limped into the All-Star break. Zimmermann was the one bright spot. The then-27-year-old was 12-4 in the first half of the season with a 2.58 ERA and three complete games under his belt.

William Yoder

About William Yoder

Will is the founder and Editor-in-Chief of The Nats Blog. He's been blogging about the Nationals since 2008.