Players to watch
PLAYERS WITH BREAKOUT POTENTIAL RB Jerick McKinnon
His rushing and receiving ability play perfectly into Kyle Shanahan’s system, so look for him to challenge his four-year TD total (12) as a Vikings reserve.
FS Adrian Colbert
His fearless physicality and ball-hawking ways secured him the free safety spot as a surprise rookie, and now he needs his first interception and many more.
CB Ahkello Witherspoon
He morphed from an inactive rookie into a bona fide starter last season, and business should pick up with Richard Sherman’s presence on the other side.
TE George Kittle
A 43-catch rookie season showed his capabilities, and more is expected from him (specifically more than 2 TDs) if injuries don’t hinder him again.
OTHER KEY PLAYERS C Weston Richburg
The former New York Giants starter must quickly develop chemistry with Jimmy Garoppolo, make defensive checks and bring his nastier, stronger vibe to the line.
WR Marquise Goodwin
Last year’s breakout season (962 yards) has him poised to become Garoppolo’s No. 1 target. He has proved to be more versatile than just a downfield threat.
ON THE HOT SEAT Arik Armstead
The 49ers have just six career sacks from their 2015 top draft pick, who has missed 18 of the past 24 games with shoulder and hand injuries. A hamstring strain at the start of training camp hindered his switch from edge rusher to the “big end” position.
Malcolm Smith
After missing all of last season (torn pectoral), Smith reported to camp with a heel injury, and if injuries persist, Brock Coyle or Fred Warner are coming for his linebacker job.
Pierre Garçon
He was on pace for 1,000 yards last season as the 49ers’ No. 1 receiver before suffering a neck injury. At 32, he’s one of the NFL’s 10 oldest active receivers.
POSITIONS OF CONCERN Edge rusher
A year after pushing Armstead out as the “Leo” pass-rusher, Solomon Thomas is to get a shot, even though he’ll also slide inside to his natural spot. DeForest Buckner could dominate from the edge in the dime defense. Cassius Marsh brings speed.
Offensive line
The 49ers hope to have upgraded a few spots on their offensive line, and it could take time to see how the new unit meshes, particularly with the additions of Richburg and right tackle Mike McGlinchey. Their task: merely protect Garoppolo and open holes for McKinnon.
Cornerback corps
Richard Sherman’s health should dictate whether the cornerback group has improved. Otherwise, the 49ers are gambling on Witherspoon’s growth, Jimmie Ward’s versatility and the untapped potential of Tarvarius Moore, Greg Mabin, Tyvis Powell and Tarvarus McFadden.