Benfica moved three points clear at the top of Liga Sagres with a 4-1 home triumph against Maritimo on Saturday.
With Porto's match against strugglers Vitoria Setubal postponed on Friday, Jorge Jesus' men had a chance to put some pressure on their title rivals.
They received an early scare though, with Brazilian Rodrigo Antonio giving Maritimo a surprise lead after 25 minutes.
Paraguayan Oscar Cardozo restored parity on 34 minutes, as both sides went into the break on level terms.
The match was changed on 65 minutes when Maritimo defender Valentin Roberge was sent off after receiving a second yellow card.
Roberge also gave away a penalty and it was Cardozo who stepped up to take the spot-kick, with the attacker making no mistake.
Cardozo sealed his hat-trick three minutes later before a late effort from Spanish substitute Rodrigo made sure of an impressive home win for Benfica.
Elsewhere, Beira-Mar upset fourth-placed Rio Ave 3-1 thanks to a terrific first half.
Goals from Serginho and Javier Balboa had Beira-Mar cruising at the break and although Tarantini pulled a goal back for Rio, Joaozinho sealed the victory with his 76th-minute effort.
Sporting Lisbon's struggles continued as they were held to a 1-1 draw at Nacional.
Isael's first-half goal handed Nacional the lead before Cedric responded in the second half for Sporting.
The day's other match saw Olhanense come from behind to draw 2-2 against Gil Vicente, with goals from Nuno Piloto and Evandro Brandao in the last 30 minutes giving the hosts a point.