The manager's exasperation after Tuesday's 7-2 loss to the Angels was evident. Bastardo's ERA is 4.56.
"He has to rise to the occasion on a situation," Sandberg said. "We need to use everybody in the bullpen, especially the way the bullpen has been used in the last 10 games with a lot of innings."
Bastardo, of course, is the least of the Phillies' imposing problems. He has fallen on Sandberg's bullpen depth chart. Should Jonathan Papelbon remain with the Phillies in 2015 - a likelihood given the team's stalled progress in trading him - his setup men would be Ken Giles and Jake Diekman. Mario Hollands, 25, profiles as a second lefty.
The Phillies must tender Bastardo a contract through arbitration, and they will do that. But Bastardo, who is making $2 million in 2014, could earn a raise that puts him between $3 million and $4 million next season. General manager Ruben Amaro Jr. failed to trade Bastardo at the deadline, and his value may never be higher.
A trade this winter makes sense. The Phillies are unlikely to carry an expensive middle-inning reliever. The bullpen construction for 2015 does hinge on Papelbon's presence.
Bastardo expressed frustration Wednesday about his lack of a stable role.
"That can go through your head," he said, "but I try not to let it go through my head." The 28-year-old reliever shrugged when asked about his future in Philadelphia.
"I don't know," Bastardo said. "I don't know if I'm going to be here next year. You never know. . . . I can't say anything about that because I don't know if I'll be here or somewhere else."
After Tuesday's game, Carlos Ruiz tried to encourage his pitcher. "Keep staying strong," Ruiz told Bastardo. The catcher then highlighted a constant Bastardo issue.
"You have to believe in your stuff," Ruiz said he told Bastardo. "The sharper you are in your head, the better stuff you'll have."
Bastardo's problem Tuesday started like many before, with a walk to the first man he faced, Josh Hamilton. He has done that 11 times in his 53 outings (21 percent). No reliever in baseball this season has walked as many of his first batters as Bastardo. No Phillies reliever since Wayne Gomes in 1999 has walked more than 11 of his first batters in a season. (Gomes issued 14.)
"Yeah, well, then other times he goes out and lights it up," Sandberg said. "I don't know if he tries to be too fine when he first gets out there or what the case might be."
"I knew the situation," Bastardo said. "I wasn't trying to hang anything over to that guy because I know with one swing they can take the lead."
The most frustrating element to Bastardo's ineffectiveness is that opposing hitters view him as a difficult test. His .191 batting average against since the start of the 2011 season ranks sixth among relievers with at least 200 innings. Just one pitcher better than Bastardo - Aroldis Chapman - is a lefty.
"I feel like I'm making good pitches to guys," Bastardo said. "But things don't go right, they don't go in my favor. There is nothing I can do about it."