RPI grad student Sebastian Castillo-Sanchez and senior Andrew Imrie went undefeated while playing No. 1 last week, winning each of their three matches in a five-day span. Play began on Wednesday with a league match at St. Lawrence, where they won 8-6 in an 8-1 team victory. They then posted back-to-back wins against Union, winning 8-3 on both Saturday and Sunday. The first match was a conference contest that RPI won 6-3 to clinch a spot in the Liberty League Tournament. The second was non-league, which the Engineers won 6-1 (shortened due to inclement weather).