Alex believes this weekend could be pivotal in the title race, with Chelsea closing in on the crown.
The Blues head into the latest round of fixtures four points clear of closest challengers Manchester United.
With just four games of the season to go, Carlo Ancelotti's side know their destiny is in their own hands.
Chelsea make the short trip to Tottenham on Saturday, looking to strengthen their standing at the summit, while United go to neighbours Manchester City hoping to keep their challenge on track.
Brazilian centre-half Alex knows the Blues could get one hand on the title this weekend should they prevail in their derby encounter and is confident the trophy will be returning to Stamford Bridge for the first time since 2006.
"I think it is our trophy to lose," he said in The Times.
"I saw Arsenal lose (2-1 away to Spurs on Wednesday) and now they are six points behind.
"I hope we can win the next game against Tottenham. Manchester United have a difficult game and if they lose, it is seven points and we have Stoke at home (the next Sunday)."
One man hoping to halt Chelsea's title push is Spurs keeper Heurelho Gomes, who was in inspired form in midweek.
Alex played with his countryman during their time together and PSV Eindhoven and knows the Blues will be facing a formidable last line of defence.
"Gomes is my good friend," he added.
"He is a fantastic goalkeeper. The first season in England for him was difficult, but he is different now and against Arsenal, brilliant."