WATCH: Nadal plays huge role in Davis Cup theatrics

There couldn’t have been a more dramatic final day at the Davis Cup quarterfinals than what unfolded on Sunday. It's fitting since this set of ties will be the final one before the new Davis Cup proposal is voted on in August.

In the blockbuster quarterfinal tie of the weekend, Spain won the final two rubbers against Germany on Sunday inside Valencia's bullring to advance to the semifinals, 3-2.

On Friday, world No. 1 Rafael Nadal won his first match since the Australian Open in strong fashion over Philip Kohlshreiber, but the tie would be even by the first day's end.

Then an intense five-set doubles match would go in the way of the Germans. Though Nadal wasn't playing the doubles match, he was as engaged as anyone.

His courtside passion was impossible to miss:

On Sunday, he dominated Alexander Zverev to level the tie at two-all. To seal the tie, it was hometown hero David Ferrer digging out a grueling, near five-hour epic over Kohlschreiber.

The defending champions French team will host the Spaniards in a highly-anticipated semifinal after taking out Italy 3-1. Lucas Pouille delivered the clinching point with a four-set win over Italy's No. 1 Fabio Fognini.

There was less drama for Croatia, with the hosts defeating Kazakhstan 3-1 after world No. 3 Marin Cilic closed out the tie over Mikhail Kukushkin with the loss of just three games.

Croatia’s opponents in the semifinal will be the United States after the Americans swept past last year’s finalists Belgium in Nashville. Belgium was missing a few of its star players including David Goffin and Steve Darcis.

The Davis Cup semifinals will be held in September following the US Open.

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