Jeff Saturday reacts to Case Keenum saying he was "shocked" to hear about the Broncos trading for QB Joe Flacco. (1:41)

ENGLEWOOD, Colo. -- After one season as the starter, Denver Broncos quarterback Case Keenum said he was "definitely shocked" and "disappointed" that the team has the framework of a trade in place with the Baltimore Ravens to acquire Joe Flacco.

The Broncos signed Keenum to a two-year, $36 million deal last March to be their starting quarterback. Denver then went 6-10 in 2018, which led to the dismissal of head coach Vance Joseph and the hiring of Vic Fangio to replace him.

The proposed trade for Flacco was Denver's first significant roster move of the offseason. Neither the Broncos nor the Ravens, or even Flacco, can formally acknowledge the trade until the start of the new league year on March 13, when the deal can be filed to the NFL.

"[Broncos general manager John] Elway called me that morning and we had a great conversation, which he didn't have to do, and I appreciated that," said Keenum, who, along with his wife, Kimberly, was a guest on Jason Romano's Sports Spectrum podcast.

"I was definitely shocked. It was a surprise for us; you know, I think probably for the first day or so that's kind of what it was. You know, for us, we're definitely disappointed. It's not something we wanted to happen. I know that everybody's doing their job and John feels like that was a chance for him to help the Broncos out.''

Behind a battered offensive line -- three starters were placed on injured reserve -- Keenum was inconsistent, as was the Broncos' offense as a whole. He finished with 3,890 passing yards and 18 touchdowns. He threw 15 interceptions, tied for the second most in the league.

Keenum finished among the bottom 10 in the NFL in Total QBR.

Elway has said since season's end that a significant improvement "on the offensive side" was one of the biggest items on the team's offseason to-do list. The Broncos have the No. 10 pick in the draft.

The Broncos will try to shop Keenum in a trade in the coming weeks, but team sources have said keeping Keenum as a backup or releasing him are also options.

Keenum, 31, was the fourth different starting quarterback for the Broncos over the past two seasons. And while they are considering all options with Keenum, he believes his time with the team is over.

"For us, it's another chapter in our lives and we're going to roll with it," Keenum said on the podcast. "We're going to approach this like I do everything in my entire life, and that it's not by accident this has happened. It's just another chapter and another opportunity to overcome some adversity in my life.

"My time with the Broncos has been really special. I have enjoyed every second of it. I have absolutely been so proud to wake up every day and to walk into that building to represent the Broncos as their quarterback. ... It was an honor."

Keenum is currently slated to count $21 million against the Broncos' salary cap for the 2019 season, which is actually more than Flacco's $18.5 million cap charge for the coming year. The Broncos must pay Keenum $7 million of his $18 million base salary, whether he's on the roster or not. The salary-cap savings if Keenum is released ($11 million) and the "dead money" hit -- a salary-cap charge for a player no longer on the roster -- of $10 million are roughly the same.

Elway expressed high hopes a year ago that Keenum could be a solution to the Broncos' quarterback question. Keenum said several times this past season that he hoped to be with the Broncos "for a long, long time."

"You know, really, it's really open-ended right now," Keenum said. "We don't know what's going to happen. There's still a lot up in the air; this is very fresh. So a lot of these emotions that we're talking about are still kind of going on, still happening. So who knows what's going to be in store. I don't for sure; God does. But we'll be ready for whatever God has in store for us next."