PHILADELPHIA -- The Phillies need somebody to replace Tyler Anderson in their rotation, even though they never really had him in the first place.

The Phillies and Pirates agreed to an Anderson trade on Tuesday, but the Bucs pivoted and sent the left-hander to the Mariners because they had concerns about the medicals of one of the Phils' prospects in the deal.

Philadelphia still has time to find another starter. Its ability to find one before Friday’s 4 p.m. ET Trade Deadline feels more important than ever, because nobody knows when Phillies right-hander Zach Eflin will pitch again.

Eflin has not pitched since July 16 because of tendinitis in his right patellar tendon. He said there is no timetable for his return.

“It’s day to day,” Eflin said before Wednesday’s game was postponed due to a COVID-19 outbreak in the Nationals' clubhouse. “I could show up tomorrow and it could be great. It all depends on how the body reacts.

“Obviously, it sucks. I was pretty depressed about it for a couple of days. At the end of the day, I just have to try to get back as soon as I can and be a good teammate. It’s progressing. Maybe a little slower than I had initially thought, but I do feel progression. … We’re just going day to day and doing everything we can to strengthen the areas around the knee.”

Eflin has thrown off a mound only once since his last start.

“The concern is not being able to throw with my right mechanics and developing bad habits, which leads to arm injuries,” Eflin said. “So we’re really just taking it day by day and trying to get it to feel as good as it can feel. [The right leg] is where all the torque comes from, so we’re just trying to get that to calm down so I can get back into the torque and the drive, and everything else will flow from there.”

If the Phillies cannot make a trade by Friday and Eflin’s right knee keeps him sidelined, the team will move forward with Zack Wheeler, Aaron Nola, Matt Moore, Vince Velasquez and Spencer Howard.

Anderson was expected to start in place of Velasquez on Thursday, which is now a seven-inning single-admission doubleheader against the Nationals.

Free-agent left-hander Cole Hamels remains available. Phillies president of baseball operations Dave Dombrowski said the team liked what it saw from Hamels nearly two weeks ago, but on Saturday, he explained the team's reservations to sign him.

“I think what we have to factor in is, what can we do now knowing that Cole, as much as we like him, might not be ready for 30-40 days?” Dombrowski said. “Because if you sign him, you're basically telling him you're giving him a spot in the rotation. I don't know right now if we are in the spot where I can 100 percent say that. In five days, six days, will I be able to say that? Perhaps.”

The Phillies will be thrilled if Eflin suddenly feels better in the next few days. Maybe he will.

“We're still hopeful that he is coming back and that we'll get him back,” Phillies manager Joe Girardi said. “And we need him back. So we're trying to get it as soon as possible. I think we take it turn by turn to where we hope that he can get back. Then, if it goes a little longer, does he need rehab starts? You've got to play all those games.”