"It should be an honor for Chicago, and MLS, to have Real Madrid take notice in one of their players," Jaime Garcia of Starting XI Player Management told MLSsoccer.com. "We are hoping Chicago can find an agreement with Real Madrid to realize Gabriel's dream of playing for this club."
ESPN sources said that the Fire rejected an initial offer from Real for Slonina after the Champions League and LaLiga winners did not bid enough for the 18-year-old. Chicago responded with a counter-offer that a source described as "ludicrous," and added the talks are now "stalled."
Other clubs reportedly interested in the teenager's services include Premier League sides Chelsea, Wolverhampton Wanderers and Southampton, but Slonina's preference is to join Real Madrid, according to his agent.
"With respect to other cubs and other offers -- we've received many and we are gracious to those clubs -- but you cannot say no to Real Madrid," Garcia said.
Slonina, whose contract expires after the 2023 MLS season, has allowed just 20 goals and posted five shutouts in 14 starts this season. He had four shutouts in 11 games of his debut season in 2021.
ESPN writer Jeff Carlisle contributed to this story.