The attacker completed a £20million transfer to Everton on Wednesday and has signed a three-and-a-half-year deal with the Toffees.
Walcott’s departure brings an end to a 12-year stay at Arsenal which included 100 goals and two FA Cups.
Bellerin and Walcott were famed as Arsenal’s speedsters with both players boasting impressive pace.
And with Walcott and the defender enjoying a special, friendly rivalry together at Arsenal, Bellerin put his own spin on his goodbye to his former team-mate.
He said: ‘Best of luck on your new journey Theo Walcott! Gonna miss all those pre-season races.’
Walcott decided to end his spell at the Emirates after failing to make a single Premier League start this season.
Despite having a close relationship with manager Arsene Wenger, the Arsenal boss agreed to sell Walcott in a bid to boost his World Cup chances.
Walcott is the second big signing of Sam Allardyce’s reign at Everton and follows £27m striker Cenk Tosun through the door at Goodison Park.
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