Wexford made it five wins from five in Division four, while Westmeath and Limerick also recorded victories.
It was top versus bottom at Innovate Wexford Park, but the home side were made to work hard for their two points, eventually defeating London 0-13 to 0-09.
Brian Malon was black carded for Wexford after 24 minutes, by which time the Yellowbellies found themselves 0-04 to 0-02 down.
The visitors kept up to the pressure to lead by three at the break, but whatever manager Seamus McEnaney said in the dressing room had an immediate effect.
Ciarán Lyng’s point made it four on the spin as they edged in front, with substitute Niall Hughes claiming the final score of the game.
Westmeath are Wexford’s closest challengers after a five-point win over Wicklow.
At half-time in Mullingar, the home side led by double scores, 0-10 to 0-05, and while Wicklow rallied late on, they were always kept at arm’s reach as Westmeath saw the game out 0-19 to 0-14.
Limerick claimed their second win of the League campaign with a 2-11 to 0-15 win over Leitrim.
Goals from Iain Corbett and Darragh Treacy in either half proved crucial at Newcastlewest, and they join Leitrim on four points.
Allianz Football League Division 4 results
Limerick 2-11 Leitrim 0-15
Westmeath 0-19 Wicklow 0-14
Wexford 0-15 London 0-09