Braga moved a step closer to ensuring a UEFA Europa League spot next season despite being held to a 1-1 draw at Nacional.
The visitors looked to be on course for all three points when substitute Helder Barbosa put them ahead 14 minutes from time, but a last-gasp Luis Alberto equaliser salvaged a point for the hosts.
Nacional are in seventh place with 36 points, while third-placed Braga have 44 points with Sporting CP only two points behind.
