The Denver Broncos' top priority for the 2014 preseason was to emerge healthy.

And while they don't have a complete complement of players as they begin preparations for the Indianapolis Colts on Sept. 7, they don't expect to be without linebacker Danny Trevathan and wide receiver Wes Welker for long.

Trevathan is expected to miss at least the first three games -- and possibly a fourth -- because of a leg injury sustained in practice on Aug. 12.

The length of Welker's absence will be determined by his progress through the league-mandated post-concussion protocol, but he ran sprints with his fellow starters before the preseason finale Thursday and also ran routes for quarterback Peyton Manning.

The Broncos got running back Montee Ball back from an emergency appendectomy. He returned to practice Aug. 19 and played against Houston four days later.

They also welcomed their No. 2 and 3 cornerbacks back to full practice work this week, and expect Chris Harris Jr. and Kayvon Webster to be at full speed and availability against the Colts.

Denver worked linebacker Von Miller back into the lineup throughout preseason and got a full possession out of him against Houston on Aug. 23 -- his first game action since tearing an anterior cruciate ligament eight months and one day earlier.

Even with Trevathan out, this team is healthier than it was at any point during the 2013 season, when it was good enough to win the AFC in spite of losing 14 starters for a combined 94 games.

A year earlier, those totals were half as large -- seven for 47 -- and unlike 2013, those Broncos did not lose two All-Pros and a future Hall of Famer as they did in 2013, when they were without Miller, left tackle Ryan Clady and cornerback Champ Bailey.

The Broncos also are deeper.

The return to health of Miller, Harris and safety Rahim Moore, and the offseason signings of safety T.J. Ward, defensive end DeMarcus Ware cornerback Aqib Talib and defensive tackle Marvin Austin left some key contributors of previous years fighting to make the 53-man roster.

"(The depth) is the strongest we've been in our tenure here," Broncos coach John Fox said. "(General manager) John Elway and his staff have done a tremendous job building that depth.

"Now it's just a matter of starting the regular season and staying healthy throughout. You have got to be fortunate in that area."

Last season, the Broncos were unfortunate, and nevertheless won 13 regular-season games and made their first Super Bowl appearance in 15 years.

With a bit better luck, they might be in position to take the last step, but they will have to navigate a schedule that includes nine games against 2013 playoff teams -- including the first three -- and only three games against teams that finished 2013 with losing records, with none before Week 10.

The Broncos appear to be better. But with such a rigorous schedule, including an opening four games against teams that were a combined 45-19 last year, they need to be.

NOTES: DT Kevin Vickerson was a starter last year, but he finds himself firmly on the bubble. Vickerson sustained a dislocated hip last November and did not see any preseason game until Aug. 23 against Houston, when he led the Broncos with five tackles. Vickerson would count $2.5 million under the salary cap if he makes the roster, including $1 million guaranteed. ... DT Mitch Unrein also is on the roster bubble, but he delivered a terrific game in Dallas that included a sack. Unrein signed a restricted free agent tender, so he would be owed $1.431 million if he makes the 53-man roster. ... DE Kenny Anunike left Thursday's game because of an elbow injury. Anunike had been one of the unexpected surprises of training camp but found some difficulty as offensive linemen began to chip him more frequently on his edge rushes. ... RB Juwan Thompson has given himself a chance to make the 53-man roster as the Broncos' fourth running back. He led the team with 143 rushing yards and also posted a team-best 166 yards from scrimmage during the preseason.