Earlier, Grigor Dimitrov converted his third match point in the 24th hour of his first time, beating Jacob Fearnley and reaching the quarterfinals.
The match led 6-4 5-4 with Dimitrov in Monday's armistice, and they resumed the game on Tuesday after Iga Swiatek beat a three-set victory with Diana Shnaider.
Bulgaria's Dimitrov eventually defeated the 23-year-old British 6-4 7-6 (7-3).
Fearnley had to serve at the start of the game to stay in the game, and despite the double fault, he was keeping Dimitrov out.
World No. 16 Dimitrov won his second match with a 6-5 run on Fearnley serving, but the Scots saved it and eventually forced a tiebreak.
Dimitrov immediately controlled the circuit breaker and won the last five points in a row.
He held a meeting with Canada's Gabriel Diallo, who defeated Britain's Cameron Norrie.
Diallo only qualified as Madrid as a lucky loser, defeating Norrie from behind – ranked 91-2-6 6-4 6-4 in the world.
Earlier, defending champion Swiatek defeated Russia's Shnaider 6-0 6-7 (3-7) 6-4 in Madrid's ninth straight game.
Swiatek in Poland was not at his best, making more than 50 uncompulsory mistakes, but she saved 11 of the 13 points she faced to give Shnaider the edge.
She will face Madison Keys, who beat her on her way to the Virgin Grand Slam title, after the Americans beat Croatia's Donna Vekic 6-2 6-3.
The highest ranking Belarusian Aryna Sabalenka and Russia's Daniil Medvedev will start action later Tuesday.
