Here is the ATP rule for MTO:
(not sure if majors have different rules)
3) Medical Time-Out
A medical time-out is allowed by the supervisor or chair umpire when the physiotherapist
has evaluated the player and has determined that additional time for
medical treatment is required. The medical time-out takes place during a change
over or set break, unless the physiotherapist determines that the player has developed
an acute medical condition that requires immediate medical treatment.
The medical time-out begins when the physiotherapist is ready to start treatment.
At the discretion of the physiotherapist, treatment during a medical time-out may
take place off-court, and may proceed in conjunction with the tournament Doctor.*
The medical time-out is limited to three (3) minutes of treatment. However, at professional
events with prize money of $35,000 or less, the supervisor may extend
the time allowed for treatment if necessary.
A player is allowed one (1) medical time-out for each distinct treatable medical
condition. All clinical manifestations of heat illness shall be considered as one (1)
treatable medical condition. All treatable musculoskeletal injuries that manifest as
part of a kinetic chain continuum shall be considered as one (1) treatable medical
A total of two (2) consecutive medical time-outs may be allowed by the supervisor
or chair umpire for the special circumstance in which the physiotherapist
determines that the player has developed at least two (2) distinct acute and treatable
medical conditions. This may include: a medical illness in conjunction with a
musculoskeletal injury; two or more acute and distinct musculoskeletal injuries.
In such cases, the physiotherapist will perform a medical evaluation for the two
or more treatable medical conditions during a single evaluation, and may then
determine that two consecutive medical time-outs are required.
4) Muscle Cramping
A player may receive treatment for muscle cramping only during the time allotted
for changeovers and/or set breaks. Players may not receive a medical time-out
for muscle cramping. In cases where there is doubt about whether the player
suffers from an acute medical condition, non-acute medical condition inclusive of
muscle cramping, or non-treatable medical condition, the decision of the Physiotherapist,
in conjunction with the tournament doctor, if appropriate, is fi nal. There
may be a total of two (2) full change of ends treatments for muscle cramping in a
match, not necessarily consecutive.
Note: A player who has stopped play by claiming an acute medical condition, but
is determined by the Physiotherapist and/or tournament doctor to have muscle
cramping, shall be instructed by the Chair Umpire to resume play immediately.
If the player cannot continue playing due to severe muscle cramping, as determined
by the Physiotherapist and/or tournament doctor, he may forfeit the
point(s)/game(s) needed to get to a change of end or set-break in order to receive
If it is determined by the Chair Umpire or Supervisor that gamesmanship was
involved, then a Code Violation for Unsportsmanlike Conduct could be issued.
5) Medical Treatment
A player may receive on-court medical treatment and/or supplies from the Physiotherapist
and/or tournament Doctor during any changeover or set break. As a
guideline, such medical treatment should be limited to two (2) changeovers/set
breaks for each treatable medical condition, before or after a medical time-out,
and need not be consecutive. Players may not receive medical treatment for nontreatable
After completion of a medical time-out or medical treatment, any delay in resumption
of play shall be penalized by Code Violations for Delay of Game.
Any player abuse of this medical rule will be subject to penalty in accordance with
the Unsportsmanlike Conduct section of the Code of Conduct.
If a player is bleeding, the chair umpire must stop play as soon as possible, and
the physiotherapist should be called to the court for evaluation and treatment.
The physiotherapist, in conjunction with the tournament Doctor if appropriate, will
evaluate the source of the bleeding, and will request a medical time-out for treatment
If requested by the physiotherapist and/or tournament Doctor, the supervisor or
chair umpire may allow up to a total of fi ve (5) minutes to assure control of the
But I seem to recall Azarenka was off court for close to 10 minutes wasn't she? It should have been 6 minutes max.
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