The Terps were unable to record a shot on goal against the Deacons in one of their worst offensive performances of the season.
Cappelletti, the Hawks' goalkeeper, registered 11 saves as the Terps couldn't break through.
The Terps already boast four different goal scorers through their first two games and look to tally more as they host Richmond on Thursday.
Locksley opened up scoring in the first half, helping push the Terps to back-to-back wins.
The Terps fell 3-1 in their first matchup with the Buckeyes back on March 4.
The Terps got some younger legs up to speed and let some more experienced ones rest.
Freshman Peyton McNamara scored two goals to help push the Buckeyes past the Terps.
Olivia Stone's second half goal sealed the win for Northwestern.