SANTA CLARA – 49ers quarterback Nick Mullens got his opportunity last season after C.J. Beathard got banged up and could not make a start on a short week.

Beathard is back on the injured list, opening the door for Mullens to build a lead in the competition for the 49ers’ backup job behind Jimmy Garoppolo.

Beathard did not practice on Tuesday, as the 49ers returned to the field after two days off following the team’s preseason opener on Saturday night against the Dallas Cowboys. Beathard sustained a thumb injury when he hit his hand on a helmet on his final pass attempt of the game.

Last season, Mullens took full advantage of his opportunity when Beathard was sidelined after five up-and-down starts. Mullens played well down the stretch of the season, giving 49ers coach Kyle Shanahan no reason to take him out of the lineup.

Mullens ended up starting the final eight games of the season. He averaged 285 yards passing per game, ranking him fourth all-time through eight games behind Patrick Mahomes, Andrew Luck and Cam Newton.

On Tuesday, Mullens completed six of his nine pass attempts, including two throws to rookie Jalen Hurd, who had another good day.

Mullens and Beathard remain in competition for the backup job. If Beathard is available to play Monday night in the 49ers' second preseason game, he is scheduled to enter the game second, behind Garoppolo.

Offensive play of the day

The 49ers have been waiting for second-year wide receiver Dante Pettis to show more consistency on the practice field. Pettis caught only one pass in 11-on-11 drills on Tuesday, but it went for 30-plus yards when he found himself wide open down the right sideline to catch a pass from Garoppolo.


Cornerback Richard Sherman was trailing the play, which appeared to be a blown coverage in the 49ers’ defensive backfield.

Defensive play of the day

Veteran Malcolm Smith and rookie Dre Greenlaw are in a battle for the starting job at outside linebacker. Smith, who has been plagued by injuries since signing with the 49ers, returned to practice after missing some time with a hamstring strain.

Smith made the top play of the day when he diagnosed a shovel pass from Garoppolo to Tevin Coleman and was there to make the stop behind the line of scrimmage.

Injury report

Tight end George Kittle is experiencing tightness in his calf and did not practice. Kittle is not expected to miss much time.

Rookie wide receiver Deebo Samuel was excused for personal reasons, the team announced.

Nose tackle D.J. Jones (knee) and tight end Levine Toilolo (undisclosed) did not practice after seeing extended action on Saturday night.

Defensive end Arik Armstead (calf), linebacker Malcolm Smith (hamstring) and running back Jeff Wilson (calf) returned to practice.

Safety Jimmie Ward was back on the practice field without pads, wearing a blue jersey to signify no contact. He is returning to work after sustaining a fractured collarbone in June.

This ‘n’ that

--Rookie Wilton Speight, the No. 4 quarterback, got his first 11-on-11 snaps of the summer in practice. He completed all three of his attempts. . .

--Left tackle Joe Staley had a devastating blindside block on cornerback Dontae Johnson on a run play. Staley immediately went to Johnson and apologized for the hit that sent Johnson crashing to the ground. . .

--Ben Garland lined up at center with the first-team offense, with Mike Person playing right guard. Reserve guard Joshua Garnett remains out of action after undergoing surgery to repair a dislocated finger on the first weekend of camp. . .

--Emmanuel Moseley lined up at nickel back with the first-team defense with K’Waun Williams and Jason Verrett out through the end of the preseason with injuries. . . .

--Veteran wide receiver Jordan Matthews, who is competing for a roster spot, dropped an easy pass at waist level from Mullens near the goal line on a play from the 22-yard line. . . .

[RELATED: Shanahan not blown away by 49ers rookie receivers’ debuts]

--Garoppolo and Matt Breida hooked up for a 10-yard touchcown against the coverage of Kwon Alexander. . .

--Defensive linemen Solomon Thomas, Kentavius Street, Jullian Taylor, Jamell Garcia-Williams and Jordan Thompson registered pressures. . .

--Linebacker Fred Warner scooped up a fumble against Tevin Coleman on one of the first running plays of the day. . .

Next up

The 49ers are scheduled to practice Wednesday at 10 a.m. before traveling to Denver on Wednesday afternoon. The club will have a day off on Thursday before practices Friday and Saturday against the Broncos.