UPDATE: This achievement will not unlock in the new Team Story mode, as confirmed by Drachen77
In case anyone here was like me and wondering why this wasn't unlocking...
This has to be done in the Final Game of a match (so you have to have already won 2 games since it's first to 3) - the key word in the description being event. I kept going 0-40 down on my first serve and coming back to win and not getting any achievements. I assumed it was glitched.
The best way to win this is early on, before the opponents get better. Serve your first game and win, then try and win on their serve too, making it 2-0. You must then go 0-40 down in the next game, so serve the ball and then stand still.
Once you're 0-40 down, it's time to start winning! The reason it's best to do this early on is that later opponents will try and force to you come into the net which makes returning their shots much more difficult.
Power-up wise, I would use the racquet which gives you more stamina, as after winning 3 or 4 points in a row you sometimes hit a dud shot and the ball goes out. If it does, you lose the game, but you still have a chance on your next serve.
You could try and win from 40-0 on their serve, but it'll be harder. If you don't manage, do the same as before on your serve when the scores are 2-2. As soon as you come back and win the event from 0-40 down the achievement should pop.
Note: It doesn't matter if you get to Deuce and then lose a point, as long as you do win overall.
This can also be done in an Xbox Live session with a friend (thanks moroniccow!)