Tyjon rejected an offer to sign professional terms at Ewood Park in order to pursue the move, having already knocked back two previous Arsenal approaches, first last summer and again in January.
Blackburn's resistance has finally broken, with the forward set to undergo a medical on Friday afternoon and Arsenal expected to pay £1m up front plus a further £2m in add-ons. A formal announcement is anticipated early next week, says the London Evening Standard.
The teenager will train with Arsenal's first team but is set to play for the club's under-21s initially, with Mikel Arteta expected to hand him some senior minutes over the course of the season.
Tyjon joined Blackburn from Rochdale in 2023 and has made three senior appearances for Rovers, the first two coming during the 2024/25 season.
Standing between Blackburn and their most promising academy product losing years of development time on the sidelines, the club had extended his scholarship contract by a year rather than risk losing him for nothing, a stopgap that ultimately failed to change his mind about leaving.
Arsenal's persistence, including reported bids across three separate transfer windows, has finally been rewarded, giving the club a versatile forward they have monitored closely since his early performances for Rovers' academy sides.
Tyjon has represented England up to under-18 level, scoring twice against Morocco last September, and was seen as one of the standout attacking talents to come through Blackburn's academy in recent seasons, contributing seven goals and two assists in 21 under-21 appearances last term.
Arsenal and sporting director Andrea Berta have prioritised strengthening the club's development pathway this summer alongside their senior signings, with Tyjon representing the kind of long-term investment the club hopes will pay off in the years ahead.