There he beat No.10 ranked Tim Mayotte, before losing in three sets to number No.14 ranked Jay Berger.
Turning pro shortly after winning the NCAA individual title, Weiss scored tour singles match wins over at the time World No. 19 Tim Mayotte and No. 31 Karel Nováček both on grass courts in 1990, over World No. 6 Ivan Lendl and No. 21 Henrik Holm on hard courts in 1993, World No. 14 Boris Becker on hard courts in 1994, and most impressively over World No. 2 Stefan Edberg on hard courts in 1992.
The following year, he would do the same at the 1981 US Open, defeating Bill Cowan of Canada, and falling again to Tim Mayotte of the United States in 5 sets in the second round.
Tim Burton | Tim Pawlenty | Tim Rice | Tim Allen | Tim Hortons | Tim Kaine | Tim Berners-Lee | Tim Tebow | Tim McGraw | Mayotte | Tim O'Brien | Tim Finn | Tim Curry | Tim Buckley | Tim Robbins | Tim Henman | Tim Conway | Tim Bowness | Tim O'Reilly | Tim Hudak | Tim Hagans | Tim Winton | Tim Russert | Tim Rattay | Tim Powers | Tim O'Brien (musician) | Tim Daly | Tim Walberg | Tim Pat Coogan | Tim Flannery |
In July 1989 he defeated world # 24 Jay Berger in Stratton Mountain, 6–2, 2–6, 6–3, in August he beat # 23 Kevin Curren in Montreal, 6–2, 2–6, 6–3, and in September he upset # 8 Tim Mayotte in Los Angeles, 6–4 3–6, 7–5.