SAN FRANCISCO -- The Philadelphia Phillies' quest to figure out what's gone wrong with right-hander Aaron Nola continues when they wrap up a three-game series against the San Francisco Giants on Sunday at AT&T Park.
The 23-year-old will be opposed by 11-game winner Johnny Cueto, who will take some unresolved issues of his own to the mound for the Giants.
Nola appeared to be the Phillies' clear-cut All-Star favorite when, on the heels of a 6-2 rookie campaign, he limited nine of his first 12 opponents to two or fewer runs this season, compiling a 2.65 ERA.
A July call-up from the minors last summer, his 3.59 ERA after the All-Star break ranked 22nd in the National League among pitchers with 10 or more starts.
He was even better than that in May, sporting a 2.31 ERA that was the league's 14th best.
But after throwing six shutout innings against Milwaukee on June 6, things have gone south in a hurry for the former LSU standout. He was pulled in the fourth inning at Washington on June 11, then lasted only three innings in his next two starts against Toronto and Minnesota.
All of a sudden, his ERA has mushroomed to 4.11, and now he faces arguably his toughest assignment of the season -- the Giants in a stadium where they have won 12 of their last 15 games.
"He'll get that back," Phillies manager Pete Mackanin predicted to reporters after the debacle in Minnesota on Tuesday. "But something is missing right now."
Nola has never faced the Giants in his fledgling career.
In an effort to get things turned around, Mackanin announced Saturday that he is going to have veteran Carlos Ruiz catch Nola on Sunday. Cameron Rupp, hero of Saturday's 3-2 win, had been behind the plate for all 28 of Nola's previous starts.
"If you have Johnny Bench on your team and he's your team's best hitting catcher," Mackanin said before Saturday's game, using the Cincinnati Reds Hall of Famer as his example. "It doesn't matter who you want catching you. You better get used to having Bench as your catcher."
Cueto, meanwhile, has seen the Phillies plenty in his career. More often than not, the experience has not been a pleasant one.
The former Reds right-hander has faced the Phillies nine times and has just one win. And that was six years ago.
He's 1-4 in the nine starts with an ERA (5.05) that's the highest among teams he has seen five or more times.
But he's 11-1 with a 2.06 ERA as a Giant, and San Francisco manager Bruce Bochy assured Saturday night he's more interested in the recent past -- Cueto has won eight in a row -- than ancient history.
"This team has played us tough," Bochy said of the Phillies, whose 3-2 win Saturday came on the heels of a 5-4 loss on Friday. "It's important for us to get another good pitching performance and win a series."