You get hooked on a bad line call at a critical point in the match and you get angry. Then what happens … does it fester in your mind and make you lose focus (and the match)? It doesn’t have to; because you can use your anger to your benefit.
I was playing a practice match with a friend and I hit a cross court forehand smack on the sideline, which he called “Out” and, when challenge, pointed to a mark 6 inches outside the line. That gave him the game and a 4-2 lead in the first set.
I do not believe he was knowingly cheating (like some, rare players do); but he frequently “sees the ball out” … especially on important points. So I calmed down and said to myself, “OK, use this energy to raise the level of your game.”
I did and won 8 of the next 9 games.
When I was in the Army in 1968, (7th Infantry Division, South Korea), I was a “shave tail 2nd Lieutenant” and was in charge of an office of 22 enlisted men, including an older sergeant, who was close to retirement.
One day, we had to dress up for visiting dignitaries; and my sergeant changed from his daily fatigues into the dress uniform, with a chest full of medals. I said, “Sergeant, I didn’t know you were a Hero!”
He said, “Lieutenant, the only difference between me and the guys they court martialed for desertion was which way we were facing on the hill when we panicked. They were facing down; so they ran away. I was facing up; so I ran up the hill.”
That true anecdote really applies to many things in life: the result depends on how you use the emotion (anger, fear, adrenaline) that invades our bodies/minds in times of stress. Either you face “up the hill” and use it … or “down the hill” and it takes over your body.
P.S. Later in that same tennis match, he made what I thought was another bad call on a first serve … and I then proceeded to double fault. So, nobody’s perfect!