Toronto Maple Leafs forward Nick Robertson is expected to miss at least four weeks after sustaining a knee injury on Saturday night. 

Robertson left Saturday's 3-2 win over the Ottawa Senators after the first period and didn't return to action.

Keefe said he's classify the timeline as "good news" after initial fears.

The 19-year-old was making his NHL regular-season debut after appearing in four games with the Maple Leafs during the NHL's Return to Play last summer. He had one goal against the Columbus Blue Jackets during the best-of-five series.

Selected in the second round of the 2019 NHL Draft, Robertson spent the past three seasons with the OHL's Peterborough Petes.