Assane Ben Fall's 89th minute strike left the Terps shocked on their home pitch as their season abruptly ended.
St. Martin won the national championship in 2018 with the Terps, and he's looking to do so once more as the NCAA tournament gets underway Thursday.
The Terps dispatched the Spartans with two first-half goals despite losing midfielder Malcolm Johnston to an apparent head injury.
The Terps are scoreless in their last two games, neither of which resulted in wins.
The Terps lost to the Buckeyes in their home-opener last season.
The junior found the back of the net for the first time in the Terps' 2-1 win over Michigan.
The Terps hope playing a difficult non-conference schedule will pay off as the Big Ten slate looms.
The Terps battled back from a deficit at halftime, knocking off the Cavaliers at Audi Field.
The freshman forward scored in his first game as a Terp and impressed players and coaches throughout opening weekend.
The Terps scored three first-half goals and held off a late charge from the Retrievers to remain undefeated.