Frattin has nine goals in his past 12 games with the American Hockey League's Toronto Marlies and joins a Leafs team that has struggled to score while going 1-6-1 since Feb. 7.
Boyce had spent his entire pro career with the Maple Leafs organization. In 17 NHL games this season, the 27-year-old winger had one goal and two points.
He joins a Columbus team that is in the middle of some major changes of its own, having dealt away Antoine Vermette and Jeff Carter earlier this week.
Also Saturday, the Maple Leafs assigned forward Jay Rosehill to the Marlies.
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