The Detroit Red Wings' preseason record fell to 2-1-2 Tuesday night with a 2-1 shootout loss to the Montreal Canadiens.
Pacioretty also scored the game's opening goal at 4:42 of the second period, beating Detroit's Jimmy Howard on a fluttering backhand attempt.
Leino scored Detroit's lone regulation goal 1:53 later, pushing a shot between Price's pads after picking up a loose puck all alone in front of the net.
The goal was the second of the preseason for the rookie who signed with Detroit after leading the Finnish Elite League in scoring last season.
The Red Wings will continue their exhibition schedule in Atlanta on Wednesday, a game that is expected to mark the return of captain Nicklas Lidstrom, who has been out since taking a puck to the face in the preseason opener.
Notes: Chris Chelios left the game with a knee injury after blocking a shot early in the third period.
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