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The world No.3 prevailed 7-5 6-7 (3-7) 6-3 in two hours and 40 minutes, and will play either Jannik Sinner in the last four after the Italian beat Felix Auger-Aliassime later in the day.

Zverev claimed the crucial break in game 11 of a tight opening set, before a love hold moved him halfway to victory.

The German broke again at the start of the second set, but Fonseca responded in the sixth game to make it 3-3.

Both players exchanged further breaks before the Brazilian, appearing in his first ATP Masters 1000 quarter-final, controlled the tie-break to level the contest.

However, Zverev grabbed another important break in game six of the decider, which ultimately proved the difference, and he let out a huge roar as Fonseca found the tape on match point.