The top two teams in Portugal, FC Porto and Benfica, played to a 2-2 draw at the Estadio Da Luz on Sunday after combining to score all four goals in the opening minutes.
Benfica entered the contest three points clear of Porto, which had played one fewer match, but the visitors took the lead through Eliaquim Mangala after eight minutes.
Nemanja Matic provided the answer two minutes later for Benfica, but Jackson Martinez scored his 12th goal of the season to restore the lead for the defending champions in the 15th minute.
The lead didn't last long, however, and Nicolas Gaitan had the home side back on level terms just two minutes later, although the fireworks came to an end and both sides had to settle for a point.
Third-place Braga could have taken advantage of the result, but instead sustained a 3-2 defeat at Nacional, leaving the club 10 points back of Benfica.
Amido Balde scored deep into stoppage time to help Guimaraes earn a 1-1 draw against Maritimo, fifth-place Rio Ave secured a 1-0 win at second-from-the- bottom Gil Vicente courtesy of Marcelo's first-half goal and Pacos Ferreira remained in fourth place by topping Academica, 1-0, with Paolo Hurtado providing the only goal in the 52nd minute.
Setubal striker Ze scored a hat trick in his team's 5-0 thrashing of Moreirense, Sporting Lisbon won for just the third time in 14 games by downing Olhanense, 2-0, while Estoril claimed a 1-0 win at Beira Mar thanks to an 11th-minute goal from Lica.