The Red Devils finally started to click in their final group game, albeit against a limited New Zealand side, after successive draws against Egypt and Iran to give them confidence heading into the knockout stage of the tournament.
A 5-1 win over the Kiwis ensured Belgium won Group G, setting them up to face one of eight third-placed teams and they were provisionally slated to play South Korea until Saturday.
But the Democratic Republic of Congo's comeback victory over Uzbekistan secured their progress and eliminated the Koreans, making Belgium's next opponents Senegal, though Debast said his side would nonetheless be prepared.
"It was a bit of a weird feeling, but we know it's Senegal now and we have, I think, three days to prepare the game," he told reporters on Sunday.
The centre-back said his teammates were looking forward to playing a side which won the Africa Cup of Nations final in January, before the title was later awarded to Morocco.
"Senegal is a really good team, I think they have some good physical and tactical parts (to their game) and they won also the African cup," Debast told reporters.
"I think it will be a good game, knowing that we also have the qualities ... if we are in good form and we continue in a positive way like our last game, I think it will be a very good game."
Debast has not yet played at the tournament due to a leg injury, but said a recent MRI scan confirmed he was continuing to recover.
"It was positive, everything is going as planned so we are positive," he said. "I feel good, today I can partially take part in the team training so, yeah, it's going good."
FIFA World Cup 2026
The 2026 World Cup is taking place from June 11th to July 19th in the United States, Canada and Mexico. The tournament features 48 national teams and is played at 16 modern stadiums.
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