However, after Denver's first two games, some of that excitement has faded.
Williams and Ball have both struggled mightily, as Ball has accumulated 40 yards on 20 carries, and Williams has just two tackles. Williams hasn't looked NFL-ready, and the same goes for Ball.
As a result, Denver hasn't been helped by any rookie. That's partly because its other rookies haven't made much of an impact either, which was expected.
There isn't any concern about third-round pick Kayvon Webster, as he has played sparingly and has done well in his limited action. All other rookies have been banged up or haven't played, so there's not much concern there.
Unfortunately for the Broncos, the same can't be said for Williams and Ball.
The Broncos have tried to give both time, but neither has used their playing time well.
Ball got a goal-line carry in Week 2 against the New York Giants, and he had green grass in front of him for what likely would have been a six-yard touchdown run.
Instead, he fumbled.
Ball's gaffe didn't cost his team, which went on to obliterate the Giants 41-23.
However, his fumble and his overall struggles brought up cause for concern. He touched the ball 12 times against the Giants, and somehow, only picked up 16 yards. His longest run went for a minuscule three yards.
In other words, he has many Broncos fans concerned.
The short-term future for Denver's running backs isn't in doubt thanks to Knowshon Moreno, who ran for 93 yards and two touchdowns on just 13 carries Sunday. Moreno has the speed and playmaking ability that Ball lacks, which he displayed on his two touchdown runs down the right sideline in Sunday's win.
Ball, on the other hand, hasn't had the chance to display his open-field skills; he hasn't come close to picking up a big run.
He has stellar vision, but he hasn't been able to explode through holes. NFL defenders are much faster than college defenders, and Ball is learning that the hard way. He is a strong, stocky back, but he lacks the acceleration and burst required to succeed.
So, there's definitely reason to be concerned, especially when you consider that running back is an easy (relatively speaking) position to transition to in the NFL.
Williams, however, plays defensive tackle, and, as Mike Klis of The Denver Post noted, it is extremely difficult to transition from college to the NFL as a defensive tackle. However, his struggles are still concerning, as he hasn't been able to make anything close to the impact he made in college.
The 28th pick in the 2013 NFL draft is unpolished, and he has a lot of work to do to reach the level he wants to reach.
So, he likely won't do much this year.
However, the future is still bright for the athletic tackle. He can change a game with his athleticism and playmaking ability, which was on display in his final season at North Carolina. He worked hard to get to this point, and with more hard work and improvement, he could solidify his position in Denver's future plans.
Ball was drafted by the Broncos to be a part of their future plans, but he was expected to make his presence felt instantly. Unfortunately for Ball, Denver might have to be patient with him as well.
He has a lot of work to do, and with Moreno poised to carry the ground game for the time being, Ball might not get many more chances this season to prove himself.
Still, the Broncos shouldn't be extremely worried about him. He has a knack for scoring and he doesn't usually cough the ball up. Once he cleans up his rookie mistakes and improves his speed, he will start to hit his stride.
Denver drafted a solid group of players, and it is lucky that it doesn't need these players to make an immediate impact. Its rookies will likely come along at some time, but this isn't the time.
With Webster, Lerentee McCray, C.J. Anderson and Quanterus Smith also rookies, it's a safe bet that at least one 2013 draftee will become a key player in Denver's future.
And, luckily for the Broncos, the same can be said about the team's first two picks.