BALTIMORE -- Not that Sunday's showdown at Camden Yards needed any added magnitude, but it will now serve as the rubber game for the Phillies' highly anticipated series with the Orioles.

The Phils followed up Friday night's electric 11-inning victory over the O’s with a 6-2 loss on Saturday afternoon. Taijuan Walker kept his club in it by holding one of MLB's most high-powered offenses to three runs over 5 2/3 innings, but unlike the previous night, Philadelphia couldn't come through with a big hit.

“He threw the ball well [in the London Series against the Mets on Sunday] and today was a good day,” manager Rob Thomson said. “I’m kind of happy with where he’s at.”

However, Thomson added there are two key areas where they still need to see improvement from Walker: His splitter and his velocity.

Coming off a solid performance in London, Walker breezed through the first two innings against the Orioles. Even in the third, he limited the damage to just one run after an infield single put runners on the corners with none out.

In the fourth, however, Walker hung a splitter right down the middle and Anthony Santander made him pay with his second homer in as many days.

That pitch -- and more specifically, the location of it -- continues to be Walker's biggest issue.

The veteran right-hander threw only seven splitters on Saturday. Walker had not thrown fewer than 13 splitters in any of his previous 39 starts with the Phillies.

“I didn't really have a feel for it today,” said Walker, who pivoted more to his curveball after the first couple innings.

Of the seven splitters he threw against the O's, one was put in the seats by Santander. Another was ripped into right field at 103.2 mph for a third-inning sacrifice fly -- that, too, was right over the plate. Two induced outs and one -- a pitch well below the zone -- resulted in a single. The other two were taken for balls.

Opposing batters are now hitting .438 (21-for-48) with eight extra-base hits against Walker's splitter this season. They hit only .205 against that pitch last year, when Walker threw it 33.2% of the time, making it his most-used offering. He's thrown it just 18% this year.

“I just think the splitter is missing,” Walker said. “I feel like all my other pitches have been really good. It's just the splitter that I usually don't give up a lot of damage on, but I feel like right now, I've been giving up a lot of hard hits on the splitter.”

A big reason for that is it's simply getting too much of the plate.

Last season, 56.3% of Walker's splitters were off the plate to one side or the other and in the lower half.

Here’s a look at his splitter locations in 2023:

But entering Saturday, only 39.4% of his splitters hit those optimal spots off the plate. Meanwhile, 43.2% of his splitters were over the plate in the lower two-thirds of the zone.

Here’s his 2024 splitter breakdown:

Though Walker has had some success leaning more on his curveball at times, including on Saturday, he knows that’s not a long-term solution.

“Most of my success in my career is from my splitter,” he said. “So I definitely want to find that and get it back.”

Walker is working diligently between starts with pitching coach Caleb Cotham and the rest of the staff in an attempt to fix the splitter. It’s an issue that Walker has dealt with -- and fixed -- at various points throughout his career.

“It's such a feel pitch,” Walker said. “So it can go away fast, but it can come back really fast, too.”

Added Thomson: “He'll figure it out. They're working on it all the time.”

In the meantime, the Phillies will shift their focus to Sunday’s series finale.

After back-to-back sellouts, another massive crowd -- with plenty of Philadelphia fans -- is expected on Sunday when Phillies ace Zack Wheeler squares off with O’s ace Corbin Burnes.

"I'm ready to go; it's going to be fun,” Thomson said. “This has been a couple of really fun two days right here -- great atmosphere and electricity in the stadium. So yeah, we'll be ready to go."