SAN FRANCISCO -- Aldon Smith didn't need long to reprise his role as a pass-rushing menace for the 49ers in Thursday night's exhibition opener.
Smith pressured Peyton Manning into a third-down incompletion to cap an optimistic opening series against the Denver Broncos.
Smith, who had a franchise-record 19½ sacks last season, pushed past All-Pro left tackle Ryan Clady and then hit Manning just enough so a third-and-19 pass failed to reach Wes Welker.
Smith celebrated by lightly tapping Manning's backside, and Smith then joined most of the 49ers' first-string defense on the sideline for the rest of the night.
Smith, the 49ers' 2011 first-round pick, had offseason surgery to repair a torn labrum. He registered no sacks over last season's final six games. LaMichael James' recovered his own third-down fumble deep in 49ers' territory, but it reignited concerns over his ball security. James lost a fumble on the 49ers' second series of the Super Bowl. This time, James never had control of the ball as he took the failed handoff from Colt McCoy on the 49ers' second series.
James started at running back in place of Frank Gore, who got the night off after suiting up for pregame warm-ups. James fared well on the opening drive with five carries for 24 yards. Starting wideouts Anquan Boldin and Marlon Moore made their debuts in a 49ers uniform. Boldin produced 10- and 4- yard receptions. Moore had a 12-yard, third-down catch that shortened Phil Dawson's ensuing field goal to 32 yards. The 49ers' third-down defense came through strong in the second quarter, as linebacker Dan Skuta produced a sack and later Michael Wilhoite combined for one with Demarcus Dobbs. Cornerback Eric Wright was signed to a one-year contract and immediately was placed on the non-football injury/illness list for undisclosed reasons. The 49ers had traded for Wright from the Tampa Bay Buccaneers nearly three weeks ago, only to nullify that deal when Wright failed a July 22 physical.
"Eric is currently tending to a personal matter, and he will join the team as soon as possible,"general manager Trent Baalke said in a statement. Wright, 28, was arrested last month for suspicion of drunken driving in Los Angeles, but no charges have been filed.
The 49ers can activate Wright at any time, but they needed to sign him before their exhibition opener so he could be eligible to start the season on the NFI/Illness list, if needed. The 49ers defense started with five defensive backs: cornerbacks Carlos Rogers, Tarell Brown and Tramaine Brock; strong safety Donte Whitner and free safety Craig Dahl. Only Brock and Dahl remained in for the second series. Others who didn't suit up for the 49ers: linebacker Patrick Willis (hand), center Jonathan Goodwin, defensive tackle Justin Smith (finger) and wide receivers Kyle Williams (hamstring) and Quinton Patton (finger). Injury replacements in the 49ers' starting lineup were center Daniel Kilgore, linebacker Wilhoite and defensive tackle Dobbs. On the same date in 1971, the 49ers made their Candlestick Park debut with a 38-24 exhibition win over the Cleveland Browns. The officiating crew was testing out communication headsets among themselves to possibly speed up on-field dialogue after plays. Former 49ers running back Roger Craig served as the honorary captain and handled the pregame coin toss. To make room for Wright on the 90-man roster, the 49ers released rookie cornerback Lowell Rose, who also got waived in the premature trade for Wright.