A tense 1-0 win has helped Vitoria Guimaraes put valuable breathing space between them and Uniao de Leiria on the Liga Sagres table.Both sides have performed well this season, with Guimaraes sitting in fifth and just one point above Leiria before kick-off on Friday.The duo can both dream of earning a Europa League place if they can maintain their good form, though Guimaraes now have a handy four-point buffer on their rivals after Joao Alves' lone strike handed his side the three points.On-loan Everton forward Joao Silva had gone close to giving Leiria the lead in the first half when his well-struck shot glanced the wrong side of the upright, but just minutes later the visitors took the lead when Alves' effort from distance beat Brazilian goalkeeper Eduardo Gottardi.Guimaraes held on for the win to put them within just one point of third-placed Sporting Lisbon, though the capital club have a game in hand.Leiria's spot on the table is under threat, with five clubs - including Sporting Braga - now within a win of knocking them from fifth spot.