SANTA CLARA, Calif. (AP) San Francisco 49ers cornerback Jimmie Ward is week-to-week with a quad strain, the team announced Tuesday. He left Sunday's loss to the Seahawks with the non-contact injury after covering a kickoff in the second quarter.
That likely leaves coordinator Jim O'Neil to find a replacement for one of the most valuable members of his secondary in time for a visit from Dez Bryant and the Dallas Cowboys' eighth-ranked offense Sunday.
Ward, the team's first-round draft pick in 2014, was off to a promising start to his third season after transitioning to cornerback full-time. He played slot cornerback and safety during his first two years.
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Third-year player Keith Reaser and rookie Rashard Robinson are competing to replace Ward should he miss Sunday's game, O'Neil said. The decision will come down to which player performs better in practice.
''It keeps you on your toes,'' Reaser said. ''You know every practice counts, every play matters, almost as if it's training camp or a game.''
O'Neil said, ''Neither one of those guys has won the job outright. So if they want it to be week-to-week every week, that's on them. If somebody wants to establish themselves ... then go do that. I'm all for it.''
Reaser was drafted in the fifth round in 2014 out of Florida Atlantic. He spent his rookie season sidelined while recovering from an anterior cruciate ligament tear in his knee. He made his pro debut last season before getting the third-most snaps among 49ers cornerbacks in 2016.
Missing his rookie year helped Reaser prepare mentally for his chance at playing time.
''Everybody has a different path in this business,'' Reaser said. ''You just try to learn as much as you can and go from there.''
Robinson, a fourth-round draft pick from Louisiana State, joined the NFL facing questions about a checkered college career and an arrest in connection with a robbery, which was later expunged from his record. He elected to enter the NFL draft instead of transferring to a new school after being kicked off LSU's team.
Robinson has a chance to start Sunday against a quarterback he faced in college, Dak Prescott, who played at Southeastern Conference rival Mississippi State. The 49ers drafted Robinson 133rd overall, two spots before the Cowboys took Prescott.
''The one thing I remember from him at Mississippi State is he was pretty mobile,'' Robinson said. ''Just got to out there, just contain him.''
The 49ers signed receiver and return man Keshawn Martin on Tuesday. He played last season with the New England Patriots. He spent his first three years with the Houston Texans after being drafted in the fourth round from Michigan State.
Martin becomes the sixth receiver on San Francisco's active roster. He took the roster spot vacated by Anthony Davis, who announced his retirement Monday. It was the second time Davis retired since June 2015. His first retirement was spurred by a concussion he suffered in 2014.
Davis rejoined the 49ers at the starting of training camp after his one-year hiatus. He sustained a concussion before the Week 2 loss to the Carolina Panthers which kept him from playing before his retirement was made official.