Lazar, who can play centre and right wing, had 38 goals and 23 assists last season, helping the Edmonton Oil Kings finish first in the Western Hockey League's Eastern Conference.
General manager Bryan Murray said Saturday he believed the Senators could get a "good player" at No. 17. He was listening to offers to move up or down in the first round, but nothing materialized.
Staying pat, Ottawa took a player NHL Central Scouting's Chris Edwards said has good puck-handling ability and offensive intelligence.
Building more scoring depth in the organization can't hurt for a team that featured Kyle Turris as its leading scorer with just 29 points.