Photo by Philadelphia Union

The Philadelphia Union announced today the signing of 23-year-old Colombian defender Geiner Martinez from Uruguayan club CA Juventud. Martinez, a center-back, inked a deal through the 27-28 campaign, which includes two options for each of the two seasons following. No fee has been announced.

Martinez will, upon receiving his P1 Visa and International Transfer Certificate, join the Union’s active squad and occupy an international roster slot, per the team’s release. He becomes the Union’s seventh active international player.

In two seasons at the senior level, Martinez has made 51 appearances, tallying four goals and nearly 4000 minutes while playing almost exclusively as a center-back. In 2025, Juventud finished 4th in the Liga Auf aggregate table, enough to earn qualification to the Copa Libertadores first round. Juventud play their first round tie against CD Universidad Catolica of Ecuador in the coming weeks.

During 2025, Martinez was crucial in helping his side defensively, keeping five clean sheets in 12 Clausura appearances. While on loan at Central Español FC, Martinez was a part of the side’s first promotion-winning team in over a decade.

This signing helps to fill the defensive gap left by Jakob Glesnes’ departure. Glesnes, a former MLS Defensive Player of the Year, was traded, along with academy forward Jamir Johnson, to LAFC earlier this offseason for a guaranteed $1.1 million, which could eventually double based on performances.

The Union also sold top-tier left back Kai Wagner this offseason to Birmingham City, which leaves a formidable void. Wagner has been atop the MLS assists charts for nearly his entire time in the league and was continuously involved in winning performances.

To help fill the holes, the Union have now brought in Martinez as well as Danish center-back Japhet Sery Larsen from SK Brann of Norway and American Finn Sundstrom from North Carolina F.C.

Larsen has played in both UEFA Champions League and Europa League qualifiers, and represented both FC Midtjylland of Denmark and FK Bodø/Glimt of Norway, both highly respected in their countries and across Europe. Larsen is a strong, attacking-minded center-back who brings a solid amount of experience to a team that has lost years’ worth within the space of a single offseason.

Sundstrom, along with Larsen, are under contract through 2028. Sundstrom, a 19-year-old acquired from the USL Championship side North Carolina F.C., has mainly played center-back in his young career. The Union traded for Sundstrom’s rights from DC United, who, in return, get a 2028 first-round MLS SuperDraft selection.

Sundstrom was nominated for the USL Championship’s Young Player of the Year award after a strong 2025 season in which he led NCFC in blocks (28) and was second in clearances (111) and tackles (38). He also displayed a strong attacking prowess, finishing the year with an 81.7% pass completion rate across over 1,000 pass attempts, good for second in his squad. Sundstrom, who will likely fill the spot of Ian Glavinovich, whose contract was mutually terminated this offseason, received his first U.S. Youth National Team call-up in August when he joined the U-20s.

Looking more at Martinez, he has been very valuable in back-to-back promotion campaigns for both Juventud and Español, where he spent the last two years.

“The experience he’s gained through earning promotion in two consecutive seasons is valuable, he is a competitor and dedicated to defending within our identity,” said Carnell in the team’s press release.

The Union are still without a mainstay option at left-back, but the signing of Geiner Martinez seems to be a key part of the Union’s re-bolstering of the defensive unit.