Hinrichs totaled 10 points and a game-high 12 rebounds to help Lafayette (12-13, 5-3 Patriot League) outrebound Navy 35-24 and outscore it in the paint 24-16.
Dan Trist had 13 and Zach Rufer chipped in 11 to round out the Leopards in double figures.
Navy (7-17, 1-7) scored the first eight points of the game, but Lafayette fought back to take a 14-12 lead on Rufer’s 3-pointer at the 11:04 mark. Lafayette led at halftime 35-20.
Lafayette shot 52.2 percent (24 of 46) while holding Navy to just 37.3 percent (19 of 51).
The Leopards led by as many as 25 points.
The Midshipmen were led by Worth Smith with 13 points, but he was the only player for Navy in double figures.