Keenan will be by his wife Wendy's side on a full-time basis as she continues her battle with pancreatic cancer, the NLL team said Monday in a release. Keenan has also taken a leave of absence from his regular full-time job in his hometown of Oshawa, Ont.
His wife was diagnosed with Stage 4 pancreatic cancer in October 2013, the team said.
Offensive coach Jeff McComb and defensive coach Jimmy Quinlan will fill in for Keenan on the bench this season. Keenan plans to stay engaged with the team and will provide input as necessary, but won't be there in person.
"Wendy said to me last week that I still have to be part of it," Keenan said. "I'm just not going to be there until further notice. I think she wants me to stay involved, just so she can too."
The Rush will kick off their season Jan. 3 at Buffalo.
"It will be a challenge this year," said captain Chris Corbeil. "There is no question Derek is the leader of this group. He is well respected and he provides a lot of guidance and a certain calmness to things."
Edmonton led the West standings last year with a 16-2 mark.
The Rush were eliminated by the Calgary Roughnecks in the playoffs.