
The 22-year-old has been a standout in the EFL Championship this season, with some stunning performances on the right wing for Omer Riza’s Bluebirds.
The 6ft1in winger is extremely flexible, having scored two goals and provided two assists in 23 games while playing on both wings and at left-back, with a direct approach that has proven challenging for defenders in the second tier of English football.
Tanner is said to have rejected down a move to Tottenham Hotspur three years ago, but he may now be willing to make the step up to the Premier League, particularly if he is assured of continuous game time.
A transfer battle could break out over the English kid who guided his team to a crucial 3-0 victory over rivals Swansea City on January 18.
Southampton reportedly admires Tanner, and his versatility is an attractive facet of his game, a must-have for the Saints, who need as much depth as possible.
He has been with Cardiff since July 2022, when he arrived from non-league outfit Lewes FC and has over two years left on his contract, but that might not prevent interested clubs from swooping.
Ivan Juric clearly needs additional acquisitions before the January transfer window shuts, as his side is perilously close to relegation, sitting at the bottom of the league with only six points from 22 games. Danish midfielder Albert Gronbaek came on loan from Ligue 1 club Rennes.

However, Fabrizio Romano has informed GIVEMESPORT that more business is expected to be handled at St Mary’s.
Tanner is a man in demand, as fellow relegation battlers Leicester City and Championship automatic promotion hopefuls Leeds United and Burnley are also keen on the London-born winger, and all four clubs are plotting bids.
Cardiff boss Riza will be eager to keep hold of Tanner as his side are in a relegation battle, and the left-footed attacker has proven to be one of his key men.
Southampton may be eyeing Tanner as an emergency replacement should their shining star, Tyler Dibling, depart this month. The Saints have reportedly slapped a £55 million price tag on their right-wing English wonderkid amid interest from Tottenham and Chelsea.