It turns out that Sergio Santos isn’t ready to return to the field yet for the Union.

Manager Jim Curtin said Wednesday that Santos suffered a flareup of a knee injury on Tuesday. That came after the Brazilian striker played 30 minutes for Bethlehem Steel on Saturday against the host Swope Park Rangers, including the winning goal in a 4-3, come-from-behind victory.

Santos had made his way back from a hip-flexor injury that put him out of action in mid-March. He trained separately from the rest of the team Wednesday.

“Felt like we’re making forward progress, and then maybe had a little bit of a setback with a little issue in his knee,” Curtin said. "We’ll get pictures taken and an MRI, and then we’ll kind of assess exactly where that’s at. But unfortunately, he trained yesterday and then wasn’t able to train today.

Curtin didn’t provide a timeline.

“Kind of out of the picture right now,” Curtin said. “It sounds like it’s an old injury that’s kind of flared up, in the knee. It happens it’s part of the game. Luckily, we have a good stable of strikers.”

Santos, the Union’s top offseason striker signing, played in the Union’s first two games of the season as a substitute, totaling 39 minutes. He hasn’t played since.

Santos probably wouldn’t be going to Los Angeles for Saturday’s game against the Galaxy (10:30 p.m., PHL17) even if he had not gotten hurt. Curtin said he wanted Santos to get more time with Bethlehem, and the long trip would have been a factor.

“That probably would have been the plan: this week, playing here with the Steel, getting 90 minutes,” Curtin said. “It would have been tough to shake up and drop someone out of the 18 after the way guys have been playing. And also, Sergio needs more fitness for sure.”

Fans invited to town hall meeting

Following up on a promise to host a roundtable discussion with “fans who are active on Twitter,” Union chief business officer Tim McDermott invited them Tuesday to “participate in an open discussion about our club” at the team’s offices in Chester at 6:30 p.m., Tuesday.

Fans can register via a link on McDermott’s Twitter page, twitter.com/TimMcDermott6. Attendance will be limited to 20 fans, who will be notified by Friday. The event will be filmed for the team’s website.