Smith had one catch for 14 yards and suffered the injury on the non-catch that Baltimore unsuccessfully challenged. Pierce ran five times for 20 yards before leaving the game.
If their losses go beyond this afternoon, it'll be two significant hits to an offense which hasn't been as affected by injuries as the defense.
Update: The Ravens just trimmed the Broncos' lead to 31-10 on a 31-yard touchdown pass to Dennis Pitta, one that Joe Flacco squeezed between two defenders to get to his tight end.
The play was reviewed and upheld, giving Baltimore its first touchdown of the day with 14:31 to go in the contest. Pitta now has six catches for 64 yards, both of which are team highs.
Update II: The Broncos have upped their lead to 34-10 on Matt Prater's 36-yard field goal with 4:32 remaining.
Denver ate tons of clock on that last possession, going 62 yards on 15 plays in 9:59.
Update III: Pitta made his second touchdown catch of the day on the Ravens' first play after the field goal - a 61-yard catch that included a couple of broken tackles and one instance where he barely remained inbounds before running the rest of the way to the end zone.
It was the Ravens' longest play of the year, and cuts the Broncos' lead to 34-17.
Pitta is up to seven catches for 125 yards and two touchdowns. Nice day in a laugher.
Update IV: It's finally safe to say the Ravens are in divisional danger. Their padding in the AFC North race is down to just one game after Peyton Manning and the Broncos dismantled the home team 34-17 at M&T Bank Stadium on Sunday.
It'll get even more interesting if the Steelers beat the Cowboys this afternoon, putting two teams (the Bengals being the other) just one game out of first with two contests to go.
Baltimore (9-5) has now lost three in a row for its first such skid since 2009 and has lost two straight at home for the first time since a four-game home slide in 2007.
It was Manning's ninth consecutive victory over the Ravens, including two playoff wins, to improve to 9-2 against Baltimore. He hasn't lost to the Ravens since Dec. 2, 2001.
Manning went 17-for-28 for 204 yards and a touchdown.