Underarm serves are perfectly legal in tennis, yet they are frowned upon. But why? When an opponent is standing deep and far behind his baseline, why not surprise him with an underarm serve. It is often viewed as “not in the spirit of the game”.

Players who use the underarm serve often get booed by fans. An underarm serve may look simple but a good underarm serve relies on disguise and surprise. But in terms of tactics, It’s no different from a short cross-court forehand or a drop shot.

What do top players think of the underarm serve?

When asked about the underarm serve, Federer said:

Underarm is definitely a tactic, I believe. Especially when guys are hugging the fence in the back. From that standpoint, you shouldn’t be ashamed if you try it out.

You just look silly if you miss it sometimes. Why not try it? The problem is in practice, you never really try it. When you come out in the big stage in front of a full crowd, it is tricky to pull off.

Here’s Nadal’s opinion on the issue.

If you do it with the goal to improve your game, or like a tactical thing, I support 100 percent. If you do to disrespect the opponent, is not a good thing.

Everybody knows internally if you are doing in a good way or in a bad way. For me is no discussion about that. Is part of the rules, you can do it 100 percent. Is about yourself, if you feel good doing or not. Depends.

There are 9 ATP Masters tournaments on the men’s tour (sometimes called ATP Masters 1000). Most Masters tournaments have a 56-player draw, except Indian Wells and Miami. Indian Wells and Miami have a 96-player draw. Paris Masters and Canadian Open have a 48-player draw.

Indian Wells and Miami Masters have a bigger draw because they are one-and-half week tournaments whereas the other Masters tournaments are one-week events. The 96 players in Indian Wells and Miami are placed in a 128-player draw. The 32 seeded players get a bye in the first round and don’t play until the first weekend.

Indian Wells and Miami Masters are called the “Sunshine Double” and they are played back-to-back over four weeks in March. Both men’s and women’s events are held at the same time at these two tournaments. Indian Wells is sometimes known as the “Fifth Grand Slam”.