As Philadelphia Union prepare to face off with Columbus Crew, a number of variables make it likely this matchup will be wildly unpredictable, and potentially a lot of fun.
First, the Crew and Union are both missing a number of key players, meaning that new faces will be able to step forward to announce themselves. Jim Curtin said as much in his midweek press conference, and Union fans will have their eyes on recent loan signing Jamiro Monteiro as a potential gamechanger. Since arriving from FC Metz, Monteiro has been training but outside of the gameday rosters as he awaits an international visa. Curtin indicated that process is nearly a close, so Monteiro will join Marco Fabián, Brenden Aaronson, Ilsinho, Haris Medunjanin, Anthony Fontana, and Ale Bedoya in competition for a midfield role.
Up front, Cory Burke's call-up to the Jamaican national team leaves only Fafa Picault and David Accam as options to start. However, the Union could get creative and move Fabián to a second striker role, clearing space for Aaronson to continue at the tip of the diamond. Curtin also indicated the team was comfortable rolling out a one-striker look if that's what personnel options suggested was the best move. That flexibility indicates a coach confident in his current crop of charges.
The Union have another big question in goal, where both Matt Freese and Carlos Miguel Coronel have looked excellent for Bethlehem Steel FC this season. Andre Blake's call-up paves the way for one young goalie to step in for his first MLS start.
The Crew are missing Gyasi Zardes, Wil Trapp, and left fullback Waylon Francis to international duty, and Zack Steffen is likely out injured. New head coach Caleb Porter can call upon experience in midfield to replace Trapp, with long-time Houston Dynamo box-to-box runner Ricardo Clark available. Patrick Mullins is likely to get the nod up front in Porter's 4-2-3-1/4-4-2 shape.
That shape becomes a lot more fluid with the ball, but defensively Columbus sets up in a very structured 4-4-2. Federico Higuain joins the striker up front and both players work tirelessly to cut off passing lanes through the midfield channels. One thing to watch for: Zardes' best quality may be his defensive aggression stepping to backwards and loose passes between center backs. Mullins is unlikely to be able to replicate this aspect of his compatriot's game, and Philly may be able to look up and over the top as a result.
A key battle to watch is on the Union's left flank, where fullback Kai Wagner will try to pin back free-running right fullback Harrison Afful. Wagner has shown a lot of growth to his game in the first three matches of the season, but Afful is as consistent as it gets bombing up the flank. His aggressive runs forward are designed to force the opposition fullback deep, and the Union's narrow midfield will need to recognize when Wagner has to drop and exploit the space Afful leaves behind him on his headstrong runs.
Overall, expect this to be an open and exciting match with both teams missing pieces that help them organize. Half of the Crew's goals will go with Zardes to US camp, and the other half are on center back Gaston Sauro's stat line, so both teams will be desperate for a goalscorer to step forward early.
Be there to see who has a breakout match at 7:30 p.m. ET on March 23 at Talen Energy Stadium. Tickets are available here.