UNB, Lisbon :
FC Porto stumbled in the Portuguese title race after losing 1-0 at Guimaraes under caretaker coach Rui Barros on Sunday.
Bakary Bouba Sare scored for Guimaraes in the fourth minute after a mistake by goalkeeper Iker Casillas, and his team then hung on for the win.
Porto also lost striker Vicent Aboubakar to a second booking late.
The loss left Porto in third place, now five points behind leader Sporting Lisbon and three behind second-place Benfica.
Porto has yet to name a replacement after firing Julen Lopetegui.
