Victor Lindelof cancelled out Adrien Silva's early opener to help Benfica to a 1-1 draw with arch-rival Sporting CP in Sunday's (AEST) Primeira Liga encounter at Estadio Jose Alvalade.
Benfica knew it could not afford to lose with Porto hot on its heels in the race for the title, but its start did not offer cause for optimism.
Goalkeeper Ederson fouled Sporting CP top scorer Bas Dost inside the area and Silva kept his cool from 12 yards, finding the bottom-left corner to open the scoring after just five minutes.
Dost then missed two chances to double his side's lead early in the second half, aiming a header over the crossbar before firing inches wide, and the Dutchman's failure to find the net would prove costly.
Referee Artur Soares Dias awarded Benfica a free-kick in a dangerous position in the 65th minute and Lindelof beat goalkeeper Rui Patricio with a sublime shot into the bottom corner to salvage a draw.
Benfica remains top of the table after this result with 72 points from 30 games, four clear of second-placed Porto, which has a game in hand. Sporting, meanwhile, occupies third place on 64 points.