Given the following context:

Roy "Tin Cup" McAvoy is a former golf prodigy who has little ambition. He owns a driving range in West Texas, where he drinks and hangs out with his pal Romeo Posar and their friends. Dr. Molly Griswold, a clinical psychologist, wants a golf lesson. She asks Roy because he knows her boyfriend David Simms, a top professional golfer. They were both on the golf team at the University of Houston. Roy is immediately attracted to Molly, but she sees through Roy's charm and resists.
The next day David Simms shows up at Roy's trailer ahead of a local benefit tournament. Roy thinks he is being invited to play, but Simms actually wants to hire him as a caddy (since Roy knows the course). During the round, Roy needles Simms about "laying up" instead of having the nerve to take a 230-yard shot over a water hazard. Simms fires back that Roy's problem is playing recklessly instead of playing the percentages. Roy brags that he could make the shot, and spectators begin making bets among themselves. Simms warns Roy that he'll fire him if he attempts the shot, and Roy does, hitting a brilliant shot onto the green. Simms immediately fires Roy.

answer the following question:

What is the nickname of the person Simms fires immediately after they hit a brilliant shot onto the green? 

Tin Cup