The Colorado Avalanche signed the RW as a free agent in October, 2005 and assigned him to the Lowell Lock Monsters.
Dan Dasilva played 3 full seasons in the WHL for the Portland Winter Hawks.
2002–03: As an 18 year old, Dasilva impressed the Portland staff. Despite not playing a great deal of minutes, he still managed to tally the 2nd most points for a rookie on Portland with 22 points (9 goals, 13 assists). Portland made the playoffs where Dasilva compiled 4 assists and 0 goals.
2003-04: Dasilva’s strong play as a rookie paid off during his 2nd season. His minutes increased and so did his scoring. Dasilva’s 56 points were the 2nd most on Portland. He scored a team leading 36 goals (8th best in the WHL) and recorded 20 assists. He also led Portland with 19 powerplay goals (4th best in the league) and 2 shorthanded goals. His scoring touch disappeared in the playoffs where he failed to score a single goal.
2004-05: During his final season in the WHL, Dasilva responded to the calls to improve his all around offensive game. He led Portland in goals (31), assists (42), and points (73). He finished in the top 20 in both goals and assists. In the 2nd to last game of the regular season Dasilva got a concussion and was forced to miss the last game of the regular season and first 3 games of the playoffs.