North announced Daw's selection on Thursday five hours ahead of its team being officially announced.
The Roos hinted at Daw's selection when they posted a tweet on their official Twitter account that said simply: "#MajakHappens".
Shortly afterwards, they confirmed his debut in an emailed statement.
However, Daw had seemed an unlikely selection on Thursday morning.
In a press conference three hours before North's announcement, North coach Brad Scott had suggested Daw's form in the VFL had not demanded selection.
"He's playing really good footy in the VFL, but he's not playing footy that is saying 'You have no choice but to pick me'," Scott said.
"Maj hasn't to this point put together a game in the VFL where he's given me no choice but to bring him in.
"He knows exactly what he has to do to force his way into our side and he hasn't done that yet, but he's very, very close."
Daw, 195cm and 97kg, is likely to play as a forward against the Lions and rotate through the middle as a ruckman when Todd Goldstein has a rest.
Daw gets his opportunity after forward Robbie Tarrant failed to complete the club's main training session on Thursday.
Daw, 22, gave fans a glimpse of his freakish athleticism in North's NAB Cup campaign this year, taking a strong mark going back with the flight of the ball against the Demons and brushing defender Steven Morris aside to kick a running goal against Richmond.
Scott's faith in forward trio Tarrant, Drew Petrie and Lachie Hansen had kept Daw from making his AFL debut.
Last season, the trio averaged a combined 6.3 goals, 14.3 marks and 5.3 tackles a game, but that has slipped to 4.7 goals, 13.3 marks and 2.7 tackles a game in this year's first three rounds.
Nonetheless, Scott had reaffirmed his faith in the trio on Thursday morning.
"I think the guys are averaging 4.5 goals a game between them and Lindsay Thomas is averaging four, so in terms of the scoring power of our forwards I think it's as potent as ever," Scott said.
Daw was selected by North in the 2010 rookie draft and was elevated to the Roos' senior list at the end of last season after showing steady development in three seasons with North's VFL affiliate Werribee.
Daw was suspended by North in February last year after lying to Scott about a night out that breached the club's rehabilitation protocols.
But Scott has since lauded the way Daw responded to his suspension, saying he had embraced the day-to-day professionalism required of an AFL footballer.
Nick Bowen covers North Melbourne news for AFL.com.au. Follow him on Twitter: @AFL_Nick
