Readers ask how instant replay can be good for tennis

	Will instant replay cut down on confrontations between players and chair umpires? Or will it smooth out the game? Clive Brunskill/Getty Images
	MAILBAG Jon Wertheim will answer questions from SI.com users in his mailbag every Wednesday. Your name: Your e-mail address: Your home town: Enter your question:

So they finally have instant replay for tennis tournaments in the United States. I think this is a great idea and it will add a new dimension to an already great sport. But so far we have only heard from players and administrators in favor of the change. Who are the people against the decision (there obviously have to be some since it took so long for the system to be put in place) and what are they saying about it? And what is your opinion on instant replay and the way they have implemented it?
-- Ashley, Madison, N.J.

Let's go right to the videotape. Let's discuss instant replay anyway. The USTA and both tours announced Monday that line-call technology will be part of tennis in North America, starting in Key Biscayne.

Several of you asked whether this "was good for the sport." Though we still want to see how it will work in practice, I think this is unquestionably a good move for the sport. Accuracy will be improved and, with any luck, the days of matches turning on a call that replays later determine to be inaccurate will be over. Plus, this will add a twist that will throw players' personalities into sharp relief.

How will it work?

• Each player will receive two challenges per set to review line calls.

• If the player is correct with a challenge, then the player retains the same number of challenges.

• If the player is incorrect with a challenge, then one of the challenges is lost.

• During a tie-break game in any set, each player will receive one additional challenge.

• Challenges may not be carried over from one set to another.

Once a player challenges, the official replay will be provided to the chair umpire. In addition, the official replay will be provided simultaneously to the television broadcast and in-stadium video boards, allowing on-site fans and television viewers the opportunity to see the live results of a player challenge.

Predictably, tennis administrators nearly tore their rotator cuffs patting themselves on the back over this announcement. But they're to be commended for letting common sense prevail and passing this bill through.

Unlike Apartheid South Africa, neither the United States nor any other country has deemed the United Arab Emirates' behavior meriting of boycott. (On the contrary, in many respects, the U.A.E. is leading the way forward to a modern, liberal Middle East.) You advance an unreasonable standard if you demand that tennis players scrutinize nation-state politics more finely than their own governments. Further, you make the common mistake (shared, at times, by the protagonists) of conflating disputes with the state of Israel with racial bigotry. The U.A.E. has not banned entry by an ethnic or religious group, it has banned entry by citizens of a particular country with which it has a dispute. Thought exercise: Suppose this tournament was being held in Peru and that Peru was denying Ecuadorian passport holders entry to Peru. Would your level of anxiety be so high?
-- Andrew, New York City

Last week's discussion about Dubai generated a lot of mail. Most of it, like Andrew's, was thoughtful and civil. I tried to respond to some of you personally, but let me just make a few points:

• A lot of you gave a "glass houses" response, noting China's human rights abuses, America's Patriot Act, apartheid, etc. Apart from being a futile and terribly subjective exercise, this isn't about which nation has a more wayward moral compass. The issue is not whether you're pro-Israel or pro-Arab. The issue is simply this: whether a country that has a blanket ban on another country's citizens (again, check out this link, which I think is terribly damning evidence) ought to be granted a sanction by a tour with an international membership.

Sports Illustrated senior writer Jon Wertheim covers tennis for the magazine and is a regular contributor to SI.com.