Keep learning, kid quarterback.

Aqib Talib has got this.

Just keep getting better, Broncos’ offense.

Von Miller and the Denver Defense has this.

In a game when Broncos quarterback Trevor Siemian moved the offense at will between the 30s but struggled to finish drives, Talib and Miller made big plays that led to two defensive touchdowns and the Denver defense defeated Andrew Luck and the Indianapolis Colts, 34-20, here Sunday at soon-to-be-renamed Sports Authority Field at Mile High.

"It's a special group we have there, no doubt,'' Siemian of the Broncos' defense that had two touchdown scores to the offense's one. "You hit the nail on the head, it's encouraging that we move the ball so well but I need to finish some of those drives and that's some of the things we will clean up.''

Talib came up with his franchise-record fifth interception scoring return and Miller finished off Luck with a strip sack that led to Broncos’ outside linebacker Shane Ray picking up the ball and returning the fumble 15 yards for a game-clinching touchdown.

Ray was playing late in place of veteran linebacker DeMarcus Ware, who suffered a fractured right forearm just below the elbow. Ware suffered the break when he blasted by teammate Von Miller's knee as they attempted to sack Luck with a minute gone in the third quarter.

After Luck led the Colts on a second-half opening scoring drive that tied the score, 13-13, the Broncos came back with their own 13-play possession that ended with a short Brandon McManus field goal.

At that point, the Broncos led 16-13, but it should have been more as they had six drives that at least reached the Indy 36-yard line.

"It's a little worrisome,'' said Broncos receiver Demaryius Thomas, who had a team-high five catches for 90 yards despite a sore hip. "You can't keep kicking field goals. It's any given Sunday, Monday or Thursday. One day a team might come out and score three touchdowns on our defense and if we kick five field goals we lose the game. We've got to figure out what we can do to get in the end zone.''

Talib knows how to get there. Early in the fourth quarter, the Colts were facing third-and-15 when Luck tried to force a pass down the middle to Phillip Dorsett. A "seven stop" is how Talib described it, meaning Dorsett ran out seven strides, stopped, turned around and ... Talib jumped him to the ball.

Talib, who was playing a couple steps behind Dorsett, read Luck’s eyes. Talib broke on the pass and snatched it before it reached Dorsett, then took off. Colts tight end Jack Doyle had a perfect angle on Talib early in the return, but the Broncos’ cornerback juked outside and stepped down the sideline for a 46-yard touchdown return.

"I was able to make the play, make a guy miss and go home,'' Talib said.

It was the fifth interception touchdown return for Talib, which is a Broncos’ record. Remarkable considering Talib is only two games into his third season with the Broncos. And he missed one game each of his first two seasons so Talib's five pick sixes have come in 32 games as a Bronco.

“Because I practice it,'' Talib said. "Ask my coach--when I get an interception in practice, I go score on it. Practice makes perfect.”

It gave the Broncos a 23-13 lead, and the score they needed to hold off the never-say-die Luck.

After throwing the pick six, Luck led his team back on a 12-play, 80-play drive that ended with a 7-yard catch and run touchdown by veteran running back Frank Gore. With a little more than 4 minutes remaining, the Broncos were only up, 23-20.

But the accurate and unflappable Siemian came through again. A 21-yard pass interference penalty against the depleted Colts’ secondary helped get the Broncos’ started. Siemian then connected with tight end Virgil Green for 18 yards. Although Green suffered a calf injury on the play and left the stadium wearing a protective boot around his left foot, the Broncos’ offense was again well inside Indy territory.

The play that all but put away the Colts was a third-and-11 completion to Thomas. Although he was tackled a couple yards short of the first down, Thomas used his left hand to keep his body prone while reaching a couple yards ahead with the ball in his right hand for a first down.

"Unbelievable to be honest with you,'' Siemian said of Thomas' performance. "he's a really tough guy and a heckuva player. It was special to watch him handle the injury and make a bunch of big plays for us.''

The Broncos again settled for a field goal. They were up 26-20 with 1:51 remaining. Broncos head coach Gary Kubiak said later he hated settling for the field goal instead of going for it on fourth-and-1 and the ball at the Indy 17 with 1:55 remaining. Pick up that yard and the game is finished.

“I’ll be honest with you, I really didn’t like my decision,'' Kubiak said. "I know that’s crazy, we won the game. I made a decision for a reason. We struggled in short yardage in the game. We struggled big time. We had the adjustments going on up front. ... I didn’t like that we missed one in the third quarter, a big one. We got knocked back and missed one, so I didn’t feel good about what we were doing offensively. I told the defense, ‘I put you in a tough position, but that’s what you’re made of.’ We should stay on the field right there. We should find a way to stay on the field.”

No sweat, coach. Von Miller was there. On the Colts’ first play, Miller – who had two half sacks earlier in the game – stormed in on Luck and knocked the ball out of the quarterback’s hands, setting up Ray’s touchdown return.

Miller had never previously sacked Luck in his career but he was credited with 3.0 in this game.

"I think it was just different energy,'' said Miller, who now has 4.0 sacks through two games. "I came into the game with the mindset I’m going to rush hard every single play, try to fight through the chips and just be there for my guys. Today, the energy was positive. I was able to get there. I was able to fight out some chips, fight through a couple bull rushes and was able to get there. We had great coverage. The ‘No-Fly Zone’ did a fabulous job today and we were able to get some sacks.”

Siemian finished the game completing 22 of 33 for 266 yards.

“I like him. I told him ‘much respect’ after the game,'' said Colts and former Broncos safety Mike Adams. "He hung in there. I got a couple good shots on him and he still stuck in there and threw the ball, got the ball off. I think he’s surprisingly a good quarterback, for a young guy just getting his second start in a real game.”

On a hot, mid-September afternoon, Bronco fans went through the highs and lows of pregame. The Broncos unveiled the retired number banners for Frank Tripucka’s No. 18, Floyd Little’s No. 44 and John Elway’s No. 7.

There were 17 Tripuckas who attended the ceremony – one grandchild missed his Sunday morning flight – on behalf of the late Frank Tripucka, the first quarterback in Broncos’ history.

Peyton Manning also wore No. 18 the previous four seasons and he was recognized on the bottom of Tripucka’s banner. Manning didn’t want to take away from the Tripuckas’ moment and stayed up in a suite during the ceremony. With a camera pointed at him, he waved to the crowd when he was introduced.

The crowd went wild during the retired number ceremony but boos were audible when Broncos linebacker Brandon Marshall was introduced during the starting lineup ceremony. Marshall again didn’t stand during the National Anthem, drawing jeers mixed with some cheers from the home crowd.

"I was expecting all boos,'' Marshall said.

His defense played well in the first half, though, as the Colts could only muster two long field goals from their great kicker Adam Vinatieri, who converted from 48 and 52 yards out.

With the Denver defense again playing to its league-leading standard carried over from their Super Bowl 50 championship last year, the Broncos’ offense missed chances to build a larger lead.

Siemian started the game 5 of 5 for 94 yards, but then missed an open Emmanuel Sanders in the end zone on his next two passes and Denver settled for a short field goal.

The Broncos grabbed a 10-3 lead on a touchdown run by tailback C.J. Anderson, who eased in untouched from 4 yards out.

Anderson had another strong gaining 74 yards on 20 carries and converting a third-and-10 by catching a short pass, breaking a tackle, gaining 11 yards and getting out of bounds with 39 seconds remaining in the first half.

Siemian then completed short passes to Jordan Norwood, Cody Latimer and Thomas to set up a 43-yard field goal by Brandon McManus with 5 seconds remaining.

McManus hooked his first field goal attempt from 54 yards, but came back to make four field goals.

Siemian was 17 of 25 for 215 yards in the first half with an interception that was again thrown along the line of scrimmage. That play came from the Colts’ red zone which prevented the Broncos from tacking on. Then again, the interceptor, Darius Butler, would have returned the pick for a score had he not pulled up after 19 yards with what a strained hamstring.

"I would not have caught him,'' Siemian said. "It was a play where either I have to eat it or hand it off or do something else. I will work had to clean that up but that was one I definitely would like to do over.''

Siemian, now 2-0 through his two NFL starts, will lead the Broncos into game 3 next week at Cincinnati to play the 1-1 Bengals. All Siemian may have to do to win his first road game is make sure the Denver defense boards the plane with him.