There is "optimism" Gerben Thijssen will recover from his heavy crash on the first night of racing at the Ghent Six Day, according to the Belgian rider's team Lotto Soudal.
Thijssen is in intensive care after three small brain haemorrhages.
The 21-year-old also fractured three ribs and a collarbone in the crash.
"Less than 18 hours after his terrible crash, Gerben was able to have a small conversation with his family," his team said on Twitter.
Britain's Mark Cavendish, who won the event with Bradley Wiggins in 2016, bounced back from his opening night crash to win the second Derny race on Wednesday.
Cavendish sat out the first madison event on the opening night after crashing in the one-lap time trial.
The 34-year-old, who this year is partnered with seven-time winner Iljo Keisse, was not seriously injured but had to withdraw from the remainder of Tuesday's racing.
Keisse and Cavendish, who has called the Ghent Six Day, the "Tour de France of track cycling", are now in sixth overall, out of 14 teams, on 58 points.
They are a lap down on current leaders, Germany's Roger Kluge and Theo Reinhardt, who have 59 points.