A team captain and second team Empacher-CRCA All-American as a senior in 2024, Ljunggren rowed exclusively with the varsity eight in his final season, helping the crew to first-place finishes at the Geiger Cup and Baggaley Bowl before competing at the IRA National Championship. He also participated in the varsity four at the Head of the Charles, where the crew finished first. As a junior, he sat in the seven seat at the IRA National Championship, where the Big Red finished fifth.