Sudden, unexpected success

I have been spending hours watching Australian Open tennis. One thing I notice is that very often, when a much-lowered ranked player plays excellently and takes the first set against a front-ranked opponent, he/she invariably fades spectacularly in the following sets and loses the match.

Said one of such players: "Maybe I started thinking about winning the match a little too soon - I'd only won the first set, there was still a long way to go."

In tennis as in life, it is often very difficult to handle sudden and unexpected success.