Broncos' Bradley Chubb out for season with torn ACL

The Denver Broncos took another blow to their 0-4 season start on Monday. Outside linebacker Bradley Chubb will miss the rest of the season with a torn ACL, Broncos head coach Vic Fangio confirmed Monday shortly after Adam Schefter broke the news.

Chubb injured his knee in the fourth quarter against the Jacksonville Jaguars, but returned to the game. Earlier he left with a calf issue and returned. The broadcast mentioned cramps, and neither Chubb nor Fangio referenced a serious issue. Fangio told reporters, via ESPN, that Chubb "had some calf issues and then I think he had another injury in his leg issue that he was able to come back from." He will now undergo surgery, per Schefter.

[Watch live local and primetime NFL games free with the Yahoo Sports app]

In his Monday meeting with the media, Fangio confirmed that Chubb will miss the rest of the season and said it was a surprise.

“He felt good enough to come back in (Sunday). And actually, he played that series pretty damn well,” Fangio said. “ ... I think he was surprised as anybody this morning when he woke up feeling the way he did.

“He’s one of our better players, obviously. He’s a tempo setter. Great player, great person, all that. So it is a loss.”

Four games into his second year he had 21 tackles, one sack and one forced fumble. He started all 16 games his rookie year with 60 tackles, a rookie team record 12 sacks, two forced fumbles and 21 quarterback hits.

He was expected to break out this season, and the Denver defense was set up for success with pieces that include linebacker Vonn Miller. Instead, it has struggled — it had zero sacks through the first three games — and the team is in a deep hole.

The Broncos lost another heartbreaker against the Jaguars, 26-24, after a late roughing penalty helped Jacksonville get a 33-yard game-winning field goal. Quarterback Joe Flacco had put the Broncos in front with a quick touchdown, but left 1:32 on the clock and the Jags took advantage. Both home losses featured questionable late calls on the Broncos that led to winning kicks.

More from Yahoo Sports:

Denver Broncos outside linebacker Bradley Chubb will miss the rest of the season. (AP Photo/David Zalubowski)