Ashton, 22, has three assists in 30 games with the NHL club this season. In 16 games with the Toronto Marlies, he has 13 goals and five assists.
Holland, 23, has 10 points (5-5) in 32 games with the Leafs and four points (3-1) in four games for the Marlies.
The Maple Leafs also assigned forward Frazer McLaren to the AHL team Wednesday. McLaren, 26, did not record a point and had 72 penalty minutes in 26 games this season.