The phrase "to stop the rot" means to take action or make changes in order to prevent a situation from getting worse or deteriorating further. Full definition
Both teams were in search of a boost, with Leeds finally stopping the rot with a win against Bristol City in the Championship after losing three straight and four in five league matches. (throughitalltogether.sbnation.com)
With most of the cast returning from the excellent Rogue Nation, which very much stopped the rot of this great spy franchise, expectations are high for Mission: Impossible - Fallout. (gamesradar.com)
Watford have fallen out of the play - off places despite leading the table little more than a month ago, with new manager Slavisa Jokanovic struggling to stop the rot at Vicarage Road following the club's bizarre turnaround in managers at the start of the campaign. (caughtoffside.com)