Jansson’s Brentford side took on second-bottom Watford at Vicarage Road on Saturday and took a 15th-minute lead through Christian Norgaard.
Emmanuel Dennis drew Watford level ten minutes after the interval but Bees captain Jansson condemned the Hornets to a tenth home defeat in a row when heading home a 95th-minute winner.
Victory put Thomas Frank’s Bees on to 39 points and in 11th place in the Premier League table, 15 points clear of the drop zone and with five games left.
Roy Hodgson’s Hornets, though, remain six points behind fourth-bottom Everton and now having played two games more.
Watford are 11 points behind fifth-bottom Leeds, both sides now having six games left.
Taking to social media after his late winner, Jansson said: “Save them goals to the important moments I heard. No words can describe the love for this team, squad and club.”
Check out the latest Premier League transfer speculation below...
7. Rooney wants Bardsley
Wayne Rooney wants to bring old friend Phil Bardsley from Burnley to Derby County, if the Rams are saved from relegation. (The Sun) | Getty Images
8. Anderson in demand
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9. Leeds linked with Dest
Leeds United could look to seal a ‘big deal’ for Barcelona full-back Sergino Dest this summer. (Pete O’Rourke) | Getty Images
10. Toon checking Sanchez
Newcastle United are ‘checking’ on the possibility of signing Robert Sanchez from Brighton this summer. (The Sun) | Getty Images