jump ball

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A method of starting play or determining possession in which an official tosses the ball up between two opposing players who jump and try to tap the ball to a teammate.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Metaphor for a contest too close to call.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun (basketball) the way play begins or resumes when possession is disputed; an official tosses the ball up between two players who jump in an effort to tap it to a teammate