Victory over Newcastle saw Arsenal return to the top of the Premier League table, three points ahead of Manchester City - though having played one game more.
"If Arsenal win next week against Fulham at home, Arsenal will win the league," Merson said on Sky Sports.
"I do (think so). I've said all season that they'll win it. It is getting tight, but I think if they can go six points clear... Everton away is a difficult game (for Man City) when six points behind."
Ex-Liverpool midfielder Jamie Redknapp added: "I think it's 50/50. I genuinely believe that. Anything could happen. We might get down to a situation with goal difference. We see the pressure.
"I watched Man City against Burnley on Tuesday night and there was a little bit of pressure in their performance. Anything can still happen."