SAN FRANCISCO -- Tyler Beede knows his stuff is good enough to play in the Majors. The challenge for him now is learning how to harness it more consistently.

The 26-year-old rookie endured his fifth consecutive rough start in the Giants’ 9-5 loss to the A’s on Wednesday afternoon at Oracle Park, securing a split of the two-game series between the cross-bay rivals.

Beede threw 80 pitches over four-plus innings, allowing four runs on eight hits while walking none and striking out five. The A’s forced Beede to work out of the stretch in each inning of his outing, scoring at least one run in the first three frames to seize an early 4-0 lead.

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“We’re just trying to get him over the hump here as far as being consistent with his execution of pitches,” manager Bruce Bochy said. “The equipment is there. I know he’s battling it, but that’s why we need to get him to the point where that confidence is there and he’s making his pitches when he has to. It’s still a work in progress. We’ll keep working.”

The Giants, meanwhile, were overwhelmed by A’s starter Homer Bailey, who allowed only two singles to Kevin Pillar over seven scoreless innings. They entered the eighth inning trailing 7-0, but they finally came alive against Oakland’s bullpen, erupting for five runs -- including a three-run shot by Mike Yastrzemski -- to cut the deficit to two.

The A’s padded their lead with a two-run ninth, clinching a 4-5 homestand for the Giants, who head to Arizona for a four-game series against the D-backs that will have implications for the National League Wild Card race.

Rotation questions will follow the Giants to Chase Field, as the back end of their staff has begun to show cracks after leaning heavily on young starters like Beede, Shaun Anderson and Conner Menez.

“It’s a challenge, but hey, I don’t mind challenges,” Bochy said. “It’s up to me to try to get this figured out. When you’re bringing up young pitchers, you’re going to have some growing pains.”

Dereck Rodriguez will be called up to pitch Thursday’s series opener, but the Giants will need another starter for Saturday. Logan Webb, the club’s top pitching prospect, is an option, but he’s only made one start above Double-A and missed 80 games after testing positive for a performance-enhancing drug earlier this season. Johnny Cueto is on the comeback trail and is scheduled to make his third rehab start Thursday, but he won’t be ready to help the Giants until September.

While Beede has shown the ability to dominate, as evidenced by his eight shutout innings against the Mets on July 19, he’s struggled to climb out of a recent rut. Over his last five outings, Beede has posted an 8.49 ERA in 23 1/3 innings and allowed eight home runs. The Giants have lost each of those starts.

“There’s no shortage of learning experiences,” Beede said. “I’ve had a lot lately. I’m no stranger to adversity and certainly being able to learn at this level will teach me a lot down the road.”

Limiting hard contact has been an issue for Beede, who entered Wednesday tied with the Orioles’ David Hess for the highest average exit velocity allowed (91.2 mph) among Major League pitchers with a minimum of 200 balls in play. Beede’s hard-hit allowed rate of 45.3 percent is also third-highest.

“The stuff’s there, but the attack just wasn’t where I needed to be in terms of getting ahead of guys,” Beede said. “No walks, but I was just in bad counts and just giving them more chances to put the ball in play with hard contact. I think just going down the road, I have to make sure that I’m focusing on having a better count leverage and attacking guys. I think we’ll be in a better situation, for sure.”

Bochy wouldn’t commit to keeping Beede in the rotation, as the Giants will have the option to replace him with Anderson, who will be eligible to come off the IL next week after missing one start with a blister on his right middle finger.

“He’s a guy that we believe in,” Bochy said of Beede. “We’ll see where we’re at five days from now.”