Chelsea boss Jose Mourinho rates Oscar ahead of Spanish ace Juan Mata.

The People says Mata and Brazil defender David Luiz are NOT among the five senior players he believes are certain starters for the Premier League kickoff.

Mourinho is thought to prefer Oscar in the No.10 role supporting a main striker, believing the Brazilian is a more attacking threat than Mata.

Only five Blues stars are certain starters for the coming season - Petr Cech, Ashley Cole, Frank Lampard, Eden Hazard and Oscar.