It brings into question whether the Phillies must look elsewhere for their primary lefty reliever in 2013.
"We ain't down on him or nothing," Manuel said. "We're going to pitch him."
Bastardo pitched to a 2.64 ERA in 58 innings last season. It has skyrocketed to 5.45 in 361/3 innings this season. His strikeouts are up but so are walks and hits allowed.
Since the start of last September, Bastardo has a 6.39 ERA, and just about every possible theory has been floated to explain his ineptitude. First, he was tipping pitches. Then there were mechanical flaws. He was pitching with a tired arm. He combated a loss of feeling in his fingers. He lacked confidence.
For what it's worth, Bastardo's velocity has not precipitously dropped. His fastball averaged 93.3 m.p.h. last season, according to Major League Baseball's Pitchf/x data. It is averaging 92.5 in 2012.
He is simply not inducing as many swings and misses with his fastball or his slider. That could be attributed to mistakes in location. With only two pitches at his disposal, both must be right for him to succeed.
"It gets back to consistency," Manuel said. "The talent is there. We've got to get him right. If we can get him back to where he was when he was pitching for us last year, he was good. He had a big-time year for us. He was my big surprise last year. I think we can get him back there - really."
Lefty Jeremy Horst has made a solid first impression with a 1.06 ERA and 20 strikeouts in 17 innings. The Phillies love the promise of Jake Diekman, who must still overcome his propensity for walks.
They could pursue a veteran lefty this winter to supplement the inexperienced options. Among the top available arms are Jeremy Affeldt, Randy Choate, Mike Gonzalez, and J.P. Howell.
Chase Utley started the Phillies' previous 30 games before a day of rest Sunday. During that stretch, Utley hit .241 with a .383 on-base percentage and .500 slugging percentage. In his last two injury-shortened seasons, Utley slugged a combined .435. Before then, he had a career .523 slugging percentage.
The major-league average in slugging was .407 entering Sunday.
It's just one sign that Utley is driving the ball better despite his chronically injured knees. Another: His 12.7 percent line-drive rate in 2011 was second-to-last in baseball. It has risen to 18.9 percent in 2012, not far off his career mark of 20.2 percent.
Utley has one season remaining on his seven-year, $85 million deal. He is owed $15 million in 2013.
The Phillies optioned infielder Hector Luna to triple-A Lehigh Valley following Sunday's win. They are expected to activate third baseman Placido Polanco (back inflammation) before Monday's game. He played three rehab games for single-A Clearwater. Kevin Frandsen has started the last 20 games at third in Polanco's absence. . . . Sunday marked the Phillies' fifth shutout of August and 10th of the season.