We've all been there at one time or another. Your back has been against the wall, and we've panicked and tried to quickly get back into the match before your opponent jumps to far ahead. But while sometimes this strategy works, more often it doesn't. The best bet to not letting your opponent take to much of a lead is simply, do not let him. Defensive tennis at a point like this is key. Instead of playing a killer forehand, or dramatic slice, or crushing a second serve, try to put the pressure back onto your opponent. Think about how you've felt in such a tight match, but instead you were on the winning side. There is pressure to hold on to the lead and not "blow it." Your opponent is like you and will feel a little pressure.
The best way to make sense of this is to think about why you're losing instead of winning this close match. In a close match, rarely is there a difference in the level of play of each player. If there is a difference in skill level, it will always show. However, a tigh match concludes that during that particular match, each player is relatively equal in ability. So why are you losing? The answer to this is commonly mistakes by you. Most points won come from unforced errors by your opponent. This is where defensive tennis comes in. Instead of taking risky shots to get back into a match, try to put the decision on your opponent instead. Get the play in play and keep a rally going. Your opponent could feel the pressure to put you away, and take the low percentage shot himself. By playing defensive tennis, it also shows a message that you are not going to play out of your game and try to cater to his. Defensive tennis shows some resiliency and that will make your opponent think twice about his confidence.