Complex sentence: Capriati was furious at a line call during the second game of the second set at 15-30 down, but after calming down, she managed to hold on, which lead to a lengthy tiebreak.
Split into simpler sentences: Capriati was furious at a line call during the second game of the second set at 15-30 down. But after calming down, she managed to hold on, which lead to a lengthy tiebreak.