The tightness of this season's football league championships was proven once again on Saturday as Sion, starting the day in bottom place, celebrated a 2-1 home win over league leaders and reigning champions St Gallen.
Sion took the lead after just 13 minutes, thanks to a goal from Deumi. The canton Valais side then made it 2-0 midway through the second half with a goal from Poueys.
Marcel Koller's team only threatened a comeback in the dying seconds of the match, with Jerron Nixon pulling a goal back a minute into injury time. But Sion held on for a win that catapulted them into fifth place.
Just three points now separate Sion from top of the table St Gallen. Even Basel, who slipped into last place following Sion's win, are just four points from top spot - with a game in hand.
Lausanne took full advantage of St Gallen's slip-up, beating Servette Geneva 2-1 to further increase the log-jam at the very top of the standings. Olivier Baudry scored both goals for Lausanne who are now level on points with the defending champions.
In Sunday's league action, Grasshoppers Zurich will have the chance to overtake both Lausanne and St Gallen if they can win away against an ailing Lugano. Basel, meanwhile, will be looking to emulate Sion's rise from the basement with victory over FC Zurich.
swissinfo with agencies