Haaland only joined Dortmund from Salzburg in January but the 19-year-old has already been linked to La Liga giants Madrid.
The Norwegian forward has scored 10 Bundesliga goals in just nine appearances, and 13 across all competitions for Dortmund.Former Barcelona star Rivaldo has backed Haaland to light up La Liga in the future and believes he does have the qualities to potentially reach the level of Brazilian legend Ronaldo.
"He is already a great player, but at 19 he could be even better in the future and become one of the best attackers in the world," Rivaldo wrote for Betfair.
"He has a lot of personality, plays without fear and looks very calm on the pitch, so he is a world-class player that still has a lot to learn and it's normal that so many clubs are chasing him.
"Some people are already comparing Haaland's style to Ronaldo Nazario and there might be some similarities as Haaland, as he's quick, fearless and scores a lot, but it's too early to start thinking he will be Ronaldo's successor .
"Ronaldo won two World Cups and participated in four. He also dazzled the world with his runs and goals, so we need time to see if Haaland can reach Ronaldo's level. But Haaland does seem to have the qualities to at least get close to my brilliant team-mate.
"Real Madrid seems to be Haaland's preferred destination in the summer and he is showing enough quality to prosper in Spanish football. His ruthlessness in front of goal is putting him in a privileged situation and Barcelona could be a good alternative option for him. He will be a great signing for the club that manages to complete his transfer.