PHILADELPHIA -- Archie Bradley is beginning to ramp up in his rehab, with the hope of rejoining the Phillies following their upcoming nine-game road trip.

The right-handed reliever, sidelined since April 11 with a strained left oblique, plans to head to Triple-A Lehigh Valley in Allentown, Pa., when the Phils depart for their three-city trip that begins on Friday in Atlanta. He'll throw some bullpen sessions next week while the team is gone, then -- if all goes well -- potentially make a couple rehab appearances before returning for the series against the Marlins beginning on May 18. He very briefly threw off a mound earlier this week, though that was just to "test some things."

"I'm feeling a lot better. I've never really had an oblique thing, so I've just kind of been doing what I've been told to do," Bradley said prior to Thursday's series finale against the Brewers at Citizens Bank Park. "It's a little different this year with the rules, as far as being able to travel and being involved, so I've just kind of been hiding inside and doing my rehab, and trying to get back as quickly as I can."

Signed to a one-year, $6 million deal on Jan. 18, Bradley landed on the injured list after just four appearances. He's still unclear exactly when he sustained the injury, saying it's not something that happened on any one particular pitch.

Even more frustrating for Bradley is the fact that his rehab was delayed about a week due to a recent bout with what he called a "head cold." Though he never had a fever and he tested negative multiple times for COVID-19, Bradley was coughing and sneezing, which kept him from coming into the building due to COVID-19 protocols.

"Realistically, it probably set me back about a week," Bradley said. "I probably could have been ready for this road trip had I not gotten sick."

Philadelphia's bullpen could certainly use the reinforcements. After posting a 3.73 ERA over 50 2/3 innings in the club's first 15 games, the 'pen had a 6.32 ERA over 47 innings in its last 15 games entering Thursday. That ranked 27th in the Majors during that span.

The Phillies have also played an MLB-most 15 one-run games this season, including seven straight after Wednesday's 5-4 win over the Brewers. Though they're 9-6 in those contests, it's not lost on Bradley that his number would have been called plenty over the past few weeks.

"It's been really tough, man. I take what I do very personally. I want to win. I was brought here to pitch and help win," said Bradley, who had not been on the IL since his rookie season in 2015. "I've been sitting inside watching a lot of games go by where I would have been a huge part in these games. I'm just one player -- and we've done a great job -- but I think I make a difference, so having to sit inside and watch some of these games go by has been very tough."

Worth noting

• Left-handed reliever JoJo Romero was placed on the 10-day injured list prior to Thursday's game with a left elbow sprain. The club recalled fellow lefty Ranger Suarez from Triple-A to take Romero's place on the roster.