Last year, Rich Harden had a 2.07 ERA and was one of the toughest pitchers to hit in the majors. This year the Cubs right-hander is not getting the same results. Against the Indians in his last outing, Harden allowed a season-high seven runs in five innings of work, boosting his ERA to 5.27, and he’s gone six weeks without a win. Nonetheless Harden remains difficult to hit:

Harden has been as dominant this season as in 2008. He owes his high ERA to ineffectiveness with runners on base:

The long ball has been a problem; with 11 homers allowed, Harden has equaled his total from last season.

He will have his work cut out for him Wednesday when he takes the mound against a Tigers club that has the sixth lowest miss percentage in the league along with the fourth best OPS when runners are on base (through Monday).

Recent focus on Jorge Posada’s catcher ERA suggests he might share some responsibility for the Yankees’ poor pitching performance. They have a 4.65 staff ERA (through Monday) that ranks 25th in the majors, and a combined 5.78 ERA with Posada crouched behind the dish. Among catchers who have caught more than 130 innings, only Cleveland’s Victor Martinez has a worse CERA (6.14).

Right-handed pitchers have accounted for much of the difference between other New York catchers and Posada. He has caught right-handers against 43 percent of their batters faced, but righties have allowed 48 percent of their extra-base hits when throwing to Posada. Fastballs that finish in the horizontal middle of the strike zone are hit hard when Posada is catching:

Next to Martinez, hitters have a higher slugging percentage against those pitches with Posada than any other regular catcher. Although Yankees catchers do not differ much in pitch-calling tendencies, Posada seems to set his fastball target a little lower than the others, resulting in fewer high heaters and more that finish in the middle zone:

In the game of inches that occurs within the strike zone, where a small difference in pitch location can change an at-bat’s outcome, Yankees right-handers locate more fastballs in the middle when Posada is the catcher.

Joba Chamberlain, scheduled starter versus the Braves on Wednesday (7 p.m. ET, ESPN2), is one Yankees righty who has flourished with Posada as battery mate. Opponents have slugged .267 against Chamberlain when Posada is catcher compared to .474 with Jose Molina and Francisco Cervelli. Posada has caught 41 percent of Chamberlain’s pitches this season.

As the halfway mark approaches, Vernon Wells is putting up numbers similar to his disastrous 2007 when he struggled with a cyst in his shoulder and hit .245 after signing a $126 million, seven-year extension. Once considered a lock to hit 20-plus home runs, Wells had just six through Monday and recently ended a 38-game homerless streak, the longest drought of his career.

The power outage has come from not being able to drive pitches at the bottom of the strike zone. Against both fastballs and off-speed pitches, Vernon’s ability to go down and get pitches has fallen apart:

After hitting 9 of his 20 home runs last year on low pitches, Wells does not have any this year. Things get even worse if the pitch is down and away, where Wells is batting just .089 (5-for-56) with no extra-base hits through Monday.

Wells was recently moved from cleanup to third in the Blue Jays lineup, but he has continued to struggle with a .238 average (10-for-42) in the three hole. As the Blue Jays wait for him to come around, the only good news is that Wells has shown an improved eye at the plate. Typically a free swinger, Wells has dropped his chase percentage from 28 percent last year to 23 percent.