The Gunners face Chelsea at the end of the month.
Silvestre said: "I think Chelsea is going to be a big test for us. It could be a decider for the league title this season.
"We are in a good position so the players are well aware of what was missing last season and everybody is focused on giving 100% for the rest of the season.
"We are in the race, and with a little improvement, we can be a real threat this season."