Daniels hurt the knee during the team's first practice. He tried to jump over a teammate and came down on his knee. Daniels had to be carted off the field. The team confirmed that he tore the ligament in his knee. He's expected to have surgery Friday.
"Not a good way to start, at all," middle linebacker London Fletcher said. "It's a big blow to our defense. Phil was a tremendous leader, excellent at playing the run, and was going to be our third-down attack guy. With him going down, it's like we're replacing two guys."
Following the morning practice, the Redskins started working on trade discussions to replace him. According to a source, talks are under way with the Miami Dolphins for Taylor, who started the offseason by asking to go to a contending team.
With Daniels done for the season and Erasmus James starting camp on the physically unable to perform list recovering from knee problems, defensive end is the thinnest position on the Redskins. The Dolphins asked for a first-round choice for Taylor before the draft while he was competing in the "Dancing With The Stars" show on ABC. It is not known what the Redskins would offer the Dolphins for Taylor.
The Redskins lost another defensive end, reserve Alex Buzbee, to a season-ending injury during their afternoon practice. Buzbee, who went to Georgetown, ruptured his Achilles tendon.
"With Phillip gone, and now Buzbee gone, there's a hole there," head coach Jim Zorn said. "And Phillip has created a big hole."
Cornerback Fred Smoot sprained his ankle during the second practice, but he's expected to only miss a week or less.
The 35-year-old Daniels is one of the team leaders on defense, and his loss hurts the team. Demetric Evans is currently behind him on the team's depth chart.
"You always want to take advantage of opportunities," said Evans, who added that Daniels "has been a big brother."
The Redskins have not been aggressive in free agency this offseason, so they would have no trouble handling Taylor's $8.1 million contract, but they also have the ability to rework the deal. After signing all 10 draft choices before the start of camp, the Redskins have more than $9 million of cap room.
Redskins executive vice president wouldn't directly address speculation that the team is pursuing Taylor.
"We haven't talked to anybody about anything," Cerrato said.
Daniels has played 12 seasons in the NFL with Washington, Chicago and Seattle. His 59 career sacks rank 17th among active players.
"The hard part is he was so ready, and he did everything that he could possibly do to not just have a great training camp but an excellent football season," Zorn said. "And now he's got a new challenge before him, and of course we have a new challenge before us."
John Clayton covers the NFL for ESPN.com. Information from The Associated Press was used in this report.