According to TSN, the deal would pay Vanek $5 million in the first two seasons, and $6.4 million in each of the following five seasons. Vanek will also receive a $5 million and $3 million signing bonus in the first two years.
"[The Oilers] knew last night that we were going to match," said Sabres GM Darcy Regier.
Said Quinn: "I think we're very unhappy with the Edmonton Oilers. . . . It's not doing the Edmonton Oilers any good what they're going today."
In an exclusive interview with TFP, Vanek's agent, Stephen Bartlett, said several teams contacted him about his client.
"I've been talking to several teams over the last week or so," Bartlett told TFP. "Things heated up with the Oilers in the last 24 hours and we worked late into the night and into this morning.
"We notified the Sabres this morning that we received and signed an offer sheet from the Oilers."
Vanek finished fifth in the NHL in goals last season with 43 in only his second season in the league. He also finished the campaign with 41 assists and 84 points.
The 23-year-old was originally drafted fifth-overall by the Sabres in the 2003 NHL Entry Draft.