Last season, 81 starting pitchers threw enough innings to qualify for the ERA title and other postseason awards. Jerome Williams was not only the worst starting pitcher, he was the worst starting pitcher to qualify by throwing at least as many innings as games his team played (162 innings in this case). He's also the worst pitcher per fWAR, fangraphs' version of the WAR statistic created primarily from components and outcomes that a pitcher can control. If you were to pick some other stat, maybe K/9 or xFIP, he wouldn't be the worst. The worst pitchers according to those stats were Jeremy Guthrie (4.72 K/9) and Jeremy Guthrie again (4.55 xFIP).
It would seem that one could make a case that Jeremy Guthrie (1.1 fWAR) was the worst pitcher in baseball last season based on the above criteria. Instead though, let's look at Jerome Williams. Jerome Williams posted just 0.3 fWAR over 169.1 innings pitched for the Los Angeles Angels last season. That is to say that he was worth about 0.3 wins more than a replacement level player, presumably someone the Angels could call up from AAA.
Williams clearly has value, as he just signed a $2.1 million contract to pitch for the Houston Astros. The 'Stros promptly slotted him into the 5th spot in the starting rotation on the depth chart according to their website. That seems about right, and we would be remiss if we didn't mention how terrible the Astros' pitching corps was last season. The group posted a total fWAR of 1.6, with starters contributing 7.1 fWAR and relievers racked up a mind boggling -5.4 fWAR.
Jerome Williams also happens to provide some options for the Houston Astros. The Astros made it known that they viewed Williams as a starter, but his flexibility was undoubtedly a big draw for them. Last season he pitched in 37 games, 25 of them as a starting pitcher. The previous year he made another 37 appearances, but only 15 of them were starts.
Williams is a heavy groundball pitcher who has posted a groundball rate below 45% just once in his entire career. He throws six pitches, but relies on just four heavily. Last season he threw his four seam fastball just under 20% of the time, and his cut fastball just over 20% of the time. His sinker made up nearly 35% of his offerings last season, and he coupled that with changeups roughly 12% of the time. His two breaking balls, a slider and a curve, combine to make up the remaining roughly 12% of pitches (all percentages have been rounded, hence it only adding up to 99%).
Williams was fairly poor as a starter, but pretty decent as a reliever last year. He posted an ERA over 5.00 as a starting pitcher, with opposing hitters posting a triple slash of .283/.345/.472 over his 138.2 IP in that role. Meanwhile, he posted a strong 2.35 ERA with opposing hitters batting .209/.254/.298 when he came into games in relief.
Williams is, in my estimation, a shrewd pickup for Jeff Luhnow, the Houston Astros General Manager. Worst case scenario, they spent $2.1 million on a guy who will eat innings and keep prospects from throwing too many major league innings before they're ready. Best case scenario, Williams pitches well enough to drum up some interest at the trade deadline and the Astros can flip him for younger talent.
Houston is a team that is very young, but also relatively far away from competing. As such, it makes sense for them to invest in players that have a chance to return some prospect value when flipped at the trade deadline. Since Williams could play a role on a contender as an emergency starter, or solid bullpen arm, he'd likely have some value at the deadline. If he doesn't, that's only $2.1 million that the Astros have to add to the league's lowest payroll.
The Astros may have signed the worst pitcher in all of baseball from last season. His repertoire and recent success as a swingman, however, has unique value to Houston given its current roster construction. Williams presents one of those intriguing low-risk, moderate-reward signings. He's not likely to break out in Houston and become 2014's version of Scott Kazmir by posting a phenomenal season for a surprise team. He can provide some value to the Astros, though, and since they stand to benefit greatly down the line whether they trade him or not, Williams is a great signing for Jeff Luhnow. Even if he's not an exciting one.
Jerome Williams is NOT the worst pitcher in Major League Baseball. He actually presents a big value opportunity to the Astros this season.