Both sides will be desperate to put more distance between themselves and the relegation zone, as 16th-placed Boavista sit level on points with Nacional, and one point behind the hosts.
That followed two consecutive defeats for Ricardo Soares's side, as they fell to a 1-0 loss away to Tondela followed by a 2-0 home defeat to second-placed Porto.
While they do sit 13th in the Portuguese top flight, Gil Vicente are by no means in a comfortable position with just one point between themselves and Boavista in the relegation playoff place, and two points separating them from the automatic drop zone.
Os Gilistas' struggles this season have largely been down to a weak attacking record, with only two sides in the division netting fewer than the 20 goals they have scored from 23 matches.
However, that recent 4-2 victory definitely shows signs of improvements for Soares's men, and he will hope to continue that with what would be a crucial win on Friday evening.
They take on a Nacional side who will be desperately searching for a win of their own, having lost their last five league matches.
Having previously sat comfortably in the middle of the Primeira Liga table, Luis Freire's side are now dangerously close to the relegation zone, with just one point between themselves and Famalicao in the automatic relegation zone.
That defeat moved them even closer to danger, with a rival in the battle for survival picking up a crucial three points, and Freire will be desperate to not let that happen again as they look to reverse their fortunes with a win over Gil Vicente.
Gil Vicente have managed to keep a fit squad throughout the season, with young forward Miullen remaining their only injury concern.
Attackers Lourency and Pedro Marques will look to build on goals last time out, having struggled to find the net so far this season.
Soares could keep his side unchanged from their last game, given the impressive performance last time out.
Similarly, Nacional have managed to avoid any major injury concerns, with Freire having a full squad to pick from for this game.
His midfield will be boosted by the return of Ruben Micael, who served a suspension last time out after picking up his fifth yellow card of the campaign.
Gil Vicente possible starting lineup:
Denis; Pereira, Nogueira, Fernandes, Talocha; Mineiro, Afonso, Goncalves; Fujimoto, Marques, Lourency
Nacional possible starting lineup:
Piscitelli; De Souza, Cesar, Kal, Witi; Ramos, Borges, Koziello; Gorre, Riascos, Matias
We say: Gil Vicente 2-1 Nacional
Nacional look devoid of any confidence right now, and even given the importance of this game, we cannot see them recording a win on Friday.
Despite a mixed run of recent form, Gil Vicente will come in with some confidence following an impressive victory last time out, and they will fancy themselves to record a crucial victory over a struggling Nacional outfit.