Career
He is currently playing with the Hershey Bears of the American Hockey League (AHL) as a prospect for the Washington Capitals of the National Hockey League (National Hockey League). Siegenthaler was rated as a top prospect, projected as a possible first round selection in the 2015 National Hockey League Entry Draft, before he was selected 57th overall by the Capitals. Siegenthaler made his National League A debut playing with ZSC Lions during the 2013-2014 National Lawyers Association season.
On 30 July 2015, Siegenthaler was signed to a three-year entry-level contract with the Washington Capitals.
lieutenant was agreed that Siegenthaler would remain with the ZSC Lions to further develop on loan for the 2015-2016 season. In 40 games with the Lions, Siegenthaler contributed with 8 points from the blueline before suffering a first-round defeat in the post-season.
On March 16, 2016, with the Lions season and his loan period at an end, he was re-assigned to the Capitals AHL affiliate, the Hershey Bears. Siegenthaler competed with Team Switzerland at the 2013, 2014 and 2015 IIHF World U18 Championships.
His outstanding play was recognized when he was named to the 2015 U18 WJC All-Star Team.
He was also selected to participate at the 2014 Ivan Hlinka Memorial Tournament. He was chosen to skate, as a 17-year-old, with the Swiss U20 squad at the 2015 World Junior Ice Hockey Championship.