A Gibraltar international, Annesley arrived at Rovers in January 2019 to initially link up with the club's Under-23s side.
The 6’4” centre back joined from Gibraltar Premier Division champions Lincoln Red Imps on a two-and-a-half-year deal through to June 2021.
Born in London, the 20-year-old was on the books of Chelsea as a youngster, before starting his senior career at non-league club Cobham.
After a short spell at Barnet, Annesley joined Lincoln Red Imps in early 2018, making his debut against Welsh side The New Saints in the Europa League.
On the international stage, the talented teenager became the first player to represent Gibraltar at every age group from Under-16s to senior level when he made his national team debut in March 2018 in a 1-0 victory over Latvia.
He's yet to make his first team debut for Rovers, but has been a regular for the Development Squad since his move to East Lancashire.