Which one?

Sychung, you need to learn how to embed correctly.

Just look at the poll options

2008 Nadal def Feder

although I'd give a few honourable mentions to...

2007 USO QF Justine Henin def Venus Williams

2003 USO SF Justine Henin def Jennifer Capriati

2003 AO SF Serena Williams def Kim Clijsters

2009 AO SF Rafael Nadal def Fernando Verdasco

'92 RG final

2003 AO SF
I could list 10 (women's) matches alone that were way better: Hingis-Graf RG 1999, Seles-Graf RG 1992, Venus-Hingis USO 1999 and 2000, Serena-Dementieva Wimbledon 2009, Venus-Kvitova Wimbledon 2014, Sharapova-Halep RG 2014, Serena-Sharapova AO 2005, Clijsters-Serena USO 2009 Hingis-Seles AO 2002, Sabatini-Graf Wimbledon 1993, Venus-Davenport Wimbledon 2005 etc, etc.

Monica slaying Graf

Let's go down to the Tennis Courts