The Portuguese manager was shown the door with just nine months at Stamford Bridge under his belt after Saturday’s 1-0 defeat against West Brom.
With former assistant Roberto Di Matteo being promoted into the 34-year-old’s position, Mata now believes that it is time for a fresh beginning in an attempt to kick-start the Blues’ campaign.
Speaking to Chelsea TV on Monday, Mata said: "I think we have to start again, we are not in a good moment.
"We are not in a good run of results but we all want to change it. I think we are ready to change."
Mata is 15/2 with Bet365 to score the first goal when Chelsea take on Birmingham City on Tuesday.
The Blues face a testing end to their season with an FA Cup replay against Birmingham followed by a battle to claim a top-four spot in the Premier League and an uphill struggle against Napoli in the Champions League, in which they trail 3-1 from the first leg.
Nonetheless, the Spain international is convinced that, despite their problematic situation after a run of just three wins in 12 league matches and the sacking of Villas-Boas, the Blues still have the quality to end the campaign on a high.
"We have a very good squad and we have two months to achieve our objectives in the Premier League, in the FA Cup and Champions League," Mata declared.