KENT The Tri-City Americans dropped into fifth place in the Western Conference standings Tuesday after dropping an 8-3 game to the Seattle Thunderbirds at ShoWare Center.
The Americans (40-25-1-3, 84 points) fell two points behind rival Spokane (86 points), which took over fourth place with a 6-4 victory over Prince George.
The Americans and Chiefs each have three games remaining in the regular season, including a key home-and-home series Friday (at Spokane) and Saturday (in Kennewick).
With the win and the Prince George loss, Seattle (24-37-7-2, 57 points) clinched a playoff spot for the first time since the 2008-09 season.
Tri-City, which gave up two short-handed goals in the first period, trailed 3-2 after 20 minutes of play.
Luke Lockhart had two of Seattles goals in the first, while Justin Feser and Malte Strömwall scored for the Americans.
Seattle then scored four unanswered goals in the second and third periods to take a 7-2 lead before Lucas Nickles stopped the onslaught with a goal at 10:09 of the third.
Connor Honey, who had two assists, would finish off the scoring for Seattle at 18:15.
The Thunderbirds played without starting goalie Brandon Glover and defenseman Evan Wardley. Both were suspended two games by the Western Hockey League for their actions in a game against Everett on Saturday.
Rookie Danny Mumaugh took over in net for the Thunderbirds and finished with 28 saves for his first WHL victory in nine starts.
Tri-Citys Troy Trombley stopped 23 of 28 shots before being relieved of his duties at 4:49 of the third. Luke Lee-Knight came off the bench to stop 10 of 13 shots.