This year, he helped his team become the first Queensland school to win the GIO Schoolboy Cup three times.
"Obviously his size," McDonnell told foxsports.com.au when asked what first caught his eye.
"There's been some strong kids there [at Keebra Park] - Mosese Fotuaika and Issac Liu -
but this kid is as strong as any.
"For a big fella, he's got very good leg speed."
Meet Devontai Seumanutafa! 👊
Devontai attended the Keebra Park Open Trial last year and earned a Canterbury Bulldogs Scholarship. He has gone from strength to strength and will now start in the National Final on Wednesday. If you think you have what it takes, register for the Open Trial at the link below http://www.keebraparkrugbyleague.com.au/keebra-park-open-trial/
Posted by Keebra Park Rugby League Academy on Friday, September 1, 2017
"The best thing about the kid is he's willing to work hard, learn and he listens ... he knows he's got a long way to go."
Seumanutafa, an Australian resident with Samoan, Tongan and Maori heritage, is on a scholarship with the Bulldogs, and will relocate to Sydney late next year to begin pre-season training.
"He's very raw," McDonnell told foxsports.com.au.
"It's going to be a work in progress but his attitude and willingness to work is a big plus for him going forward."