Caught behind Morgan Reilly, Jake Muzzin and Mark Giordano, Sandin's injury last season could not have come at a worse time. Suffering a knee injury in mid-March, Sandin was healthy enough to play against Tampa in round 1 but Sheldon Keefe felt it would be unfair to throw him into the fire after not having played for 2 months.
If you're logical, you'd agree with Keefe, given how long Sandin had not played, it would've taken him a few games to get up to speed, something you don't have time for in the playoffs. Not only did the injury send Sandin sliding down the depth chart, but it also limited his negotiating power for his new contract.
A further limitation to his new contract is that his countryman Timothy Liljegren re-signed with the Leafs for 2-years at $1.4M per season. Everyone has expected and predicted that their new contracts would be similar in both term and dollar value. Given that Liljegren is all but a regular NHLer now, Sandin's deal will likely come in at slightly less per season - if a new deal is reached.
In Montreal today, the day before the draft, Kyler Dubas was asked about the possibility of an offer sheet for Sandin, to which he said:
There's no indication that the Leafs do not want to keep Sandin, but it's clear that Dubas has had enough of his young players trying to dictate how the negotiation plays out. Of course, an offer sheet on Sandin will handicap the Leafs should the team choose to match, and it would be a shame to lose Sandin when most of their blueline is in their mid to late 30s, but it wouldn't be the first time Dubas and Co. manage to wiggle out of a sticky situation.