As Denver left tackle Garett Bolles was waving to the crowd during his cart ride off the Broncos stadium field Sunday, he wasn’t saying goodbye.

He was just saying thanks and see you in a couple weeks. At least that would have been the appropriate salutation following the eventual diagnosis of his left ankle injury.

A magnetic resonance imaging (MRI) exam Monday morning, which followed X-rays at the stadium Sunday evening, revealed a deep bone bruise just above Bolles’ left ankle, a source told 9NEWS.

But no fracture was detected. Bolles, whom the Broncos selected out of Utah with their No. 20 overall selection in the first round during the 2017 NFL Draft in April, is expected to miss a couple weeks, per the source.

Broncos head coach Vance Joseph confirmed the "lower leg bruise" and that Bolles was "week to week," during his day-after-game press conference Monday. A source also said tests shows Bolles suffered a high ankle sprain but the Broncos limit their diagnoses to bone bruise.

"We're very lucky that it wasn't serious,'' Joseph said. "So we dodged a bullet in my opinion there.''

That means Bolles will miss the Broncos’ game Sunday at Buffalo and probably the next game in two weeks (October 1) against the Oakland Raiders.

But with a bye in week 5, Bolles could have a chance to return either October 15 against the New York Giants.

Bolles suffered the injury on a goal-to-go running play midway through the third quarter of the Broncos’ 42-17 upset trouncing of the Dallas Cowboys. After slipping off his block, Bolles was on all fours when his left ankle was inadvertently kicked by Cowboys’ defensive tackle Brian Price, who was moving in to tackle ballcarrier Jamaal Charles.

The Broncos’ medical team attended Bolles on the field and initially thought there was a chance of a fracture in the shin bone near the ankle, which is why the team announced during the game he had a lower leg injury. It turns out the trauma in the area was a deep bone bruise. Bolles' wife Natalie tweeted out it appeared her husband had suffered a high ankle sprain and a source told 9News a high ankle sprain was part of the injury, but Joseph contained the injury to a bone bruise.

Donald Stephenson initially replaced Bolles on for the next two goal line plays, including Trevor Siemian’s 2-yard flip to Virgil Green for a touchdown that gave the Broncos a 28-10 lead.

On the next series, Allen Barbre, who had just been cleared from a concussion, came in and played the rest of the game at left tackle.

"We just thought yesterday with the game where it was to play Barbre being a better run blocker for us at the end of the game,'' Joseph said. "But year, (Stephenson) is our swing tackle. he plays left and right.''

Barbre has played plenty of left guard and right tackle in his 11-year NFL career but the Broncos acquired him in a trade from Philadelphia on the eve of training camp with the understanding he could play left tackle in a pinch.

As they always seem to be, the Broncos are in a pinch at offensive tackle. And they are about to play a Buffalo Bills team that is no joke on defense, especially when it comes to rushing the quarterback. The Bills sacked Cam Newton six times in a 9-3 loss at Carolina on Sunday.

Barbre did throw a road-grader block that sprung C.J. Anderson for a 16-yard touchdown run that stretched the Broncos’ lead to 35-10. But the key at left tackle is protecting the blindside of Siemian. What's peculiar about the Broncos' offensive line group is its heavy on interior blockers (guards and centers) and light on tackles. Barbre is primarily a guard who backed up starter Max Garcia the first two games at left guard. Connor McGovern is a guard-center. Billy Turner, who didn't dress the first two games, is a guard. That leaves Stephenson as the only true backup tackle. But when confronted with an emergency at left tackle Sunday, the Broncos didn't go with Stephenson.

It wouldn't be a surprise if the Broncos alter their offensive line mix and pick up an experienced tackle.

"We have lots of options that I won't share today,'' Joseph said. "But we have lots of options.''