The biggest threat to the Union’s momentum might be upcoming national team games

As great as the Union’s perfect start to the season has been, there are signs of when it might come to an end.

The March 29 game at Lionel Messi’s Inter Miami is an obvious candidate, given the immense firepower of not just the superstar but his teammates. Veteran striker Luis Suárez has four goals and five assists in seven games so far, even at age 38; and 21-year-old midfielder Telasco Segovia has been a breakout young star.

But the game before then could be just as much of a concern. The Union’s March 22 game vs. St. Louis SC is in the middle of a FIFA window for national team games, as MLS once again plows through the spring to fit the Leagues Cup in the summer.

Six Union players will be gone that weekend for various tournaments and friendlies: goalkeeper Andre Blake (Jamaica), right back Frankie Westfield (United States under-20s), defensive midfielders Jesús Bueno (Venezuela) and Danley Jean Jacques (Haiti), attacking midfielder Dániel Gazdag (Hungary), and striker Tai Baribo (Israel).

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That means Sunday’s game against Nashville SC — the Union’s only game this year on traditional TV as of now (2:25 p.m., Fox29, Fox Deportes, Apple TV) — will be the last time the full squad plays together until the end of the month.

The Union have long anticipated that moment, even if they might have hoped that Baribo or Bueno might not get called up. But Baribo’s six-goal start to the season moved him back up Israel’s depth chart, and Venezuela called Bueno even though he hasn’t played much.

As significant as it will be to lose Baribo and Gazdag, the Union have depth at their positions. Bruno Damiani would step in at striker, and Indiana Vassilev or Cavan Sullivan would step in at attacking midfield. (Vassilev doing so would be neatly symbolic, as new manager Bradley Carnell brought him over from St. Louis after coaching him there.)

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But the biggest loss will be Blake, as it always is when he’s not in net. If how last year went is an indication, Andrew Rick will step in. It might not be, though, since Carnell has intentionally brought new eyes to his work.

When Carnell was asked in a news conference Friday whether he has started planning yet, he didn’t give much of a hint.

“The assessment started already through preseason,” he said. “Then we get a starting group out there, but that’s not to say that the other group isn’t ready. We’ve been playing scrimmages behind closed doors, we’ve been challenging each other, we’ve been getting guys Union II minutes.”

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That includes Rick and Sullivan, who started in Union II’s season opener against New England last weekend. Nathan Harriel also started at right back as he wraps up his rehab from a thigh injury.

It was a scoreless tie in regulation, and Rick made two saves including an 88th-minute penalty kick. New England then won a penalty shootout tiebreaker to get an extra standings point (that’s a MLS Next Pro league rule), with Rick making one save on five attempts.

“Everything is as expected,” Carnell said. But he never said whether he has made his decision yet about whether Rick or Oliver Semmle will get that start.

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The rare TV broadcast wasn’t the only reason Sunday’s game was circled the moment the schedule came out. It will be a homecoming for Nashville manager B.J. Callaghan, who has deep ties to the area.

The grandson of former Villanova basketball coach Jack Kraft grew up in Ventnor City, N.J., then played college soccer at Ursinus from 1999 to 2002. After that, he coached at his alma mater, then St. Joseph’s, then Villanova from 2003 to 2012.

In 2014, Callaghan joined the Union’s coaching staff, and stayed until 2019 when the U.S. men’s national team hired him. He worked for Gregg Berhalter through last summer’s Copa América, and briefly became the head coach in 2023 between Berhalter’s tenures. The U.S. won the Nations League title and finished fourth in the Gold Cup during his tenure.

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Berhalter’s tenure ended in a crash at the Copa, and Callaghan’s move to Nashville wasn’t officially announced until afterward. But it was an open secret through the summer that he was on his way, no matter the results.

Sunday will be Callaghan’s first game on the Subaru Park sideline since he left the Union’s coaching staff, and his first game on any sideline in Philadelphia since the 2019 Gold Cup. (The U.S. men haven’t played in town since then.)

“It was a team that I was a fan of before I was a professional soccer coach; it’s a club that I would say gave me my first [professional] opportunity,” Callaghan said of the Union. “It will just be nice to see people that supported you along the way you were working your way through the coaching pathway. You do it upon a lot of people, and it will be nice to see those people and give them an opportunity for me to say thank you.”

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