Zach Wilt: Advanced metrics, Adam Jones and plate discipline

June wasn't kind to Adam Jones. The Orioles centerfielder hit just .237/.248/.386 with four home runs and 20 RBIs after hitting .311/.344/.546 in May and .327/.350/.522 in April. Jones' batting average dipped from .319 on May 31 to .292 on June 30. On July 4, Jones did something at the plate that he hadn't done in 45 games: He drew a walk. The coverage of Jones' walk-less streak combined with his declining numbers led to much debate about his plate discipline this season. I took a look at some of the numbers to see how this season has compared to his performance at the dish in previous years. Not surprisingly, Jones is near the top of the list in fewest pitches seen per plate appearance. This season he ranks 10th with 3.57 P/PA and as a result has walked just nine times in 348 plate appearances this season. That's just one walk per 38.6 plate appearances or one walk about every 9.6 games. The free swinger that comes to mind when I think lack of walks is Vladimir Guerrero. Over his 16 seasons in the big leagues, Guerrero walked 737 times in 9,059 plate appearances, that's a walk every 12.29 plate appearances. According to FanGraphs.com's PITCHf/x Plate Discipline data, Jones has swung at 44.2 percent of the pitches he's seen outside of the strike zone this season, a career high. In 2012, that number was 40.4 percent and has hovered around that total over the previous three seasons. By comparison, Omar Infante and Mike Napoli, two guys who share Jones' .339 wOBA this season, have swung at 26.7 percent and 26.1 percent of the pitches they see out of the zone, respectively. Overall, Jones has swung at 57.8 percent of all the total pitches he's seen this season. Remarkably, he's been able to make contact with 61.6 percent of the pitches he's seen outside of the zone, 86.7 percent of the pitches in the zone and 76.1 percent of the total pitches he has swung at this year. Because of his high contact rate, Jones' strikeout total remains low. In 375 at-bats this season, Jones has struck out just 73 times and ranks 43rd on baseball's strikeout total list. As I examined Jones' numbers dip in June, I assumed that the strikeout total would be to blame, however his 22 Ks in June are only three higher than his total in May and three less than his best month, April. The biggest difference for Jones from month to month has been his dip in batting average on balls in play. In April, Jones recorded an amazing .393 BABIP, that declined to .323 in May and in June it went down to .258. It's tough to say the cause of the decline in BABIP. Is it luck? Was Jones not able to make as much solid contact on pitches out of the zone? Is he being pitched to differently? It could be any number of things. Still, Jones has been one of the Orioles' most clutch hitters this season. Coming into Monday night, Jones was hitting .397/.413/.543 with 21 RBIs in high-leverage situations this season and .310/.310/.552 in the ninth inning. If there are ducks on the pond, Jones will likely bring them around. In 109 plate appearances with runners in scoring position, Jones is hitting .324/.339/.467 this season. But I'm sure you already knew that after his go-ahead home run off Mariano Rivera on Sunday. Zach Wilt blogs about the Orioles at Baltimore Sports Report. His views appear here as part of MASNsports.com's season-long initiative of welcoming guest bloggers to our pages. All opinions expressed are those of the guest bloggers, who are not employed by MASNsports.com but are just as passionate about their baseball as our roster of writers.