• Andy Roddick considers Serena Williams' loss to Roberta Vinci at the 2015 US Open the biggest upset in tennis history.
• Roddick highlights Williams' strong form and pursuit of the Calendar Grand Slam as factors contributing to the shock.
• Roddick also reflects on his own career upsets, including victories over Pete Sampras and Roger Federer.

Andy Roddick, a former US Open champion and tennis analyst, identified Serena Williams' defeat to Roberta Vinci in the 2015 US Open semi-final as the most shocking result in tennis history. Williams was heavily favored, aiming for the Calendar Grand Slam after winning the Australian Open, French Open, and Wimbledon earlier that year. Vinci's victory, however, prevented Williams from achieving this feat, making it a significant upset.

• What: Serena Williams, aiming for a Calendar Grand Slam, lost to Roberta Vinci in the 2015 US Open semi-final.
• Who: Serena Williams, Roberta Vinci, Andy Roddick, Pete Sampras, Roger Federer.
• When: US Open 2015 (Serena's loss), 2001 Miami Open (Roddick's win vs. Sampras), Roddick's last year on tour (win vs. Federer).
• Where: US Open (Flushing Meadows, New York), Miami Open.

The article focuses on Andy Roddick's perspective on what constitutes a major upset in tennis. His highlighting of Serena Williams' loss to Roberta Vinci underscores the unpredictable nature of sports, especially when a player is on the cusp of achieving a historic feat. The analysis also delves into Roddick's own career, showcasing his surprising victories against top-ranked players, adding a personal dimension to the discussion of upsets.

Serena Williams, you had it, winning three Slams coming in, in form coming in...everything you would want was in her corner, and nothing about the [Roberta] Vinci win, besides her playing a very smart, strategic match and using what she had, made any sense.

For me, getting rid of the cobwebs because you idolized someone and actually going to work is a hard thing to do.

Andy Roddick's reflections on Serena Williams' stunning US Open loss to Roberta Vinci provide an insightful perspective on the concept of upsets in tennis. His own experiences with surprising victories further enrich the discussion, reminding us that even the most dominant athletes can face unexpected challenges. Whether future Grand Slam events will produce similar shocking results remains to be seen, but the element of surprise is an inherent part of the sport.