Data below is based on 162,846 return points from 2022 to 2023 (WTA 89,925, NCAA-W 72,921)…
While college women players had a slightly higher 1st Serve % (NCAA-W 65% vs WTA 62%), the results show a considerable difference in favor of the pros.
Iga Swiatek won 56% of the 980 points she played at the 2022 US Open. As a baseliner, we would expect that she won by outlasting her opponents from the backcourt.
The greatest variance happens on the return of serve. The fewest winners and most errors are hit on the return than on any other specific rally length. Looking at the return differential of -17% in another way, WTA players make almost 10 return errors to every winner.