Estadio Deportivo reported Tottenham representatives were in attendance for the Europa League quarter-final second leg, and it's believed Haidara was their target after they were named on the scouting list (h/t Sport Witness).
The 20-year-old is the latest prospect to emerge from the Austrian outfit, to whom he moved from his native Mali in 2016. He is a well-rounded central midfielder who can also function out wide.
Spurs would have likely been impressed with what they saw from Haidara. He netted in a 4-1 win to help send Salzburg into the Europa League semi-finals and was named WhoScored.com's man of the match for his efforts:
Tottenham manager Mauricio Pochettino could do with boosting his reserves in central midfield. Mousa Dembele, 30, has endured injury woes this season. And the ranks start to look constricted considering Eric Dier and Victor Wanyama are more defensively minded, and Harry Winks has made only nine Premier League starts this term.
Haidara has scored six goals in all competitions this season and recorded six assists, featuring largely in Salzburg's engine room but also turning out on the right side of their midfield.
The youngster isn't renowned for his scoring touch, but Haidara rose to the fore when it counted to send in a critical long-range strike against Lazio on Thursday.
That goal and Haidara's overall performance in what was a hugely memorable result for the Austrian outfit will have likely made an impression back in north London.
In March, Salzburger Nachrichten reported of Spurs' interest in the Mali international, who made his senior debut for the national team in a 2018 FIFA World Cup qualifier against Ivory Coast in October (h/t Scouts in Attendance):
The biggest obstacle for Tottenham is Haidara is also said to be a target for one of Salzburg's sister clubs, RB Leipzig, who are said to have marked him down as a successor to Liverpool-bound Naby Keita.
Salzburg have helped refine talents like Keita, Sadio Mane and Dayot Upamecano, and Spurs appear determined to become the next club to benefit from the three-time defending Austrian Bundesliga champions' production line.