Scott Alexander, Wilmer Font are concerns in the Dodger bullpen

Closer Kenley Jansen, who is struggling to regain the consistent velocity and command of his usually devastating cut fastball, is not the only source of concern in the Dodgers bullpen.

Left-hander Scott Alexander threw so many of his sharp-breaking sinkers into the dirt in Wednesday night’s 16-6 loss to the Oakland Athletics that manager Dave Roberts referred to them as “scuds,” or surface-to-surface missiles.

Right-hander Wilmer Font’s inability to put hitters away with two strikes was painfully evident again in the ninth inning, when his 11th pitch of a grueling at-bat by Jed Lowrie was slammed into the right-field seats for a three-run home run that padded Oakland’s already huge lead.

Neither of the relief stumbles cost the Dodgers the game. An off-night by starter Alex Wood, who was clearly still weakened by the effects of the food poisoning he contracted at a San Francisco sushi restaurant over the weekend, put the Dodgers in a 7-2 hole by the time Alexander entered in the sixth.

But Alexander was acquired from Kansas City in January with the expectation that he would be a key component of the late-inning bridge to Jansen, and Font, who struck out 178 in 134 1/3 innings at triple-A Oklahoma City, could be a valuable long-relief asset if he could pair results with his stuff.

Their numbers are not pretty: Alexander has a 10.38 ERA in 4 1/3 innings of his first five appearances this season and has retired only 11 of the 21 hitters he has faced. Font has a 13.50 ERA in 10 innings of his four games and has been tagged for three homers.

Alexander walked Marcus Semien to lead off the sixth inning Wednesday night and gave up singles to Mark Canha and Lowrie, the latter hit knocking in a run. Canha scored on one of the two wild pitches Alexander threw, as the A’s pushed their lead to 9-2.

Roberts, asked if he had any concerns with Alexander’s struggles to locate the strike zone, mulled the question for several seconds before finally acknowledging the obvious.

“Yeah,” he said. “Scott is a guy who throws a heavy dose of sinkers to the bottom of the zone, and a guy like that, you would expect to be efficient, pound the strike zone and put the ball on the ground. Right now, he’s having a hard time getting ahead of hitters and being consistent in the strike zone.

“There were some scuds in there tonight. He’s working through some things mechanically. I can’t speak to the confidence. But I know it’s in there. We’ve seen it from the other side. It could be one pitch or something. There were some good throws tonight. We have to run him back out there and regain that confidence.”

Is it a release-point issue? A mechanical issue? An inability to start the pitch in the spot that will best harness the natural movement of his signature pitch?

“No, I think it’s just adjustments I need to make,” Alexander said. “I don’t think there’s any one thing. Just in general, I have to be better.”

Font gave up a two-run homer to Matt Chapman in the eighth inning and four more runs and four hits, including Lowrie’s final three-run dagger, in the ninth. Four of the six hits he allowed came on two-strike pitches. Nine of the 15 hits he has given up this season have come on two-strike pitches.

One of those two-strike blows came on the 14th pitch of an at-bat by Andrew McCutchen, who crushed a three-run, walk-off homer to give the San Francisco Giants a 7-5, 14-inning win on Saturday.

“The thing with [Font] is he’s throwing strikes, but when you get to two strikes at this level, you have to put guys away or induce soft contact,” Roberts said. “He’s having a hard time getting through an inning without getting his pitch count up. Guys have a way of spoiling pitches and seeing him more in that at-bat, and that’s leading to some slug.

“So this is a steep learning curve for Wilmer. He’s been in some spots we couldn’t keep him out of. He’s learning on the run, he’s competing, but it’s a tough league.”

mike.digiovanna@latimes.com

@MikeDiGiovanna