SEATTLE — When the Phillies arrived here late Sunday night, they were missing two-fifths of their starting rotation.

It might stay that way until after they leave Wednesday.

Zack Wheeler and Zach Eflin were still on the COVID-19 restricted list Monday night, as the Phillies began a three-game series with the Seattle Mariners. Manager Joe Girardi was unable to provide much clarity on their status but suggested they might not be cleared to return until after the series.

“My hope is that we could maybe get one or two of them back in L.A.,” Girardi said. “I don’t know if it will happen here.”

The Phillies don’t have a starting pitcher for Wednesday’s matinee finale against the Mariners or Thursday night’s opener at Dodger Stadium. Ranger Suárez and Aaron Nola were lined up to start the first two games against the Mariners. Kyle Gibson, who started Sunday, is scheduled to pitch Friday night in Los Angeles.

If neither Wheeler nor Eflin is cleared in time to fly to Seattle and pitch Wednesday, left-hander Bailey Falter is the likeliest candidate to fill in. Falter last pitched Friday for triple-A Lehigh Valley. He has tossed 5⅓ scoreless innings in two starts since getting sent to the minors last month.

Asked when the Phillies think they might get Wheeler or Eflin back for the series against the Dodgers, specifically whether it may be in time for Thursday night’s game, Girardi declined to say.

“Not sure,” he said. “It’s all I can give you, really.”

A player can be placed on the COVID-19 list for various reasons, including testing positive, exhibiting symptoms, or being identified as a close contact of someone who has the virus. Vaccinated players must be cleared by MLB to be reinstated. Unvaccinated players aren’t cleared until they submit two negative PCR tests.

The disruption to the Phillies’ pitching plans comes at a time when all five starters are pitching well. Since April 18, Nola, Gibson, Eflin, Suárez, and Wheeler have combined for a 2.95 ERA in 17 games entering Monday night. In the first two turns through the rotation, they posted a cumulative 5.68 ERA in 10 games.

“I would’ve been surprised if we would’ve been top of the line right out of the gate because three of our starting pitchers, for nobody’s fault, were a little behind [in spring training],” president of baseball operations Dave Dombrowski said last week. “I didn’t really expect them to be up to their normal par, and our starting pitching scuffled early. Now, they’ve straightened that out and are throwing the ball much better.”

No-luck Nola

In his last four starts, Nola has allowed six runs in 25⅓ innings (2.13 ERA) on 17 hits and three walks while striking out 29 batters.

Yet the Phillies are 0-4.

“It doesn’t make sense,” Girardi said. “He’s on a pretty good run right now. It’s just the quality of his three pitches and his ability to expand [the strike zone] when he has the opportunity and get people to chase. It’s been really good.”

Central to Nola’s success, as usual, is his curveball. Opponents are hitting .162 against his breaking ball, typically a bellwether pitch for whether he will be at his most effective.

Lately, though, Nola’s changeup has been sharp, too.

“And that’s really important for him to have both,” Girardi said. “It’s hard to be a two-pitch pitcher in this league, unless your stuff is just elite.”

Extra bases

Shortstop Didi Gregorius, sidelined with a sprained medial collateral ligament in his left knee, is traveling with the team. He’s feeling better, but the Phillies won’t have a timetable for his return until he resumes baseball activities. ... Monday night was only the Phillies’ 17th game ever against the Mariners, fewer than any team except the Kansas City Royals (15) and Los Angeles Angels (13). It’s their first trip to Seattle since 2017. ... A leftover from Sunday: With his home run in the first game against the New York Mets, Bryce Harper has gone deep three times on Mother’s Day, tied with Albert Pujols, Joey Votto, Carlos Santana, and Brandon Belt for most among active players. ... Chase Utley is teaming up again with Jimmy Rollins. Utley will be a guest analyst on TBS’ pre- and postgame show on May 17, working alongside Rollins, Curtis Granderson, and host Lauren Shehadi. ... Nola (1-3, 3.38 ERA) will face reigning AL Cy Young Award winner Robbie Ray (2-3, 4.38) at 9:40 p.m. Tuesday.