Arsenal and Man Utd have both sent scouts to watch CSKA Sofia defender Valentin Antov, according to reports in Bulgaria .
The 19-year-old has attracted interest from a number of European clubs, with West Ham also believed to be monitoring his progress.
Antov has become a regular in the Sofia side, making seven appearances so far this season and providing one assist.
He is a centre-back by trade, but can also operate in front of the back four as a defensive midfielder.
Representatives of the interested Premier League clubs have flown to Bulgaria to watch him in action against Ludogorets on Sunday.
Antov holds the record at Sofia for the club's youngest ever debutant at just 14 years old, in a match where he was also handed the captains armband for the final 25 minutes.
He has also already been capped at international level, making his first appearance for the Bulgarian senior side as a substitute in a qualifier with Kosovo in March.
Among his achievements include an award for the Bulgarian youth footballer of the year in 2018.
Meanwhile Arsenal are still interested in Juventus centre-back Daniele Rugani despite sacking their manager Unai Emery.
The Gunners attempted to sign the 25-year-old in the summer but baulked at Juve's asking price of over £30 million.
Rugani first came onto Arsenal's radar under Emery, but he remains a target.
Arsenal have been dogged with defensive issues in recent times, and Rugani has been identified as a potential solution.
William Saliba is already set to join Arsenal permanently next summer from St.Etienne, but further reinforcements are needed, with the club not convinced over David Luiz.
Much of Arsenal's movements in the transfer market will depend on their managerial situation.
Freddie Ljungberg is currently in interim charge, but Brendan Rodgers has been linked with the post.
