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SANTA CLARA – Cornerbacks Tramaine Brock and Chris Culliver did not practice Tuesday due to minor leg issues.
That opened the door for Chris Cook, coming off four unimpressive seasons with the Minnesota Vikings, to add a new wrinkle to his game.
In 34 games played, including 29 starts, Cook has never intercepted a pass in the NFL. During a 7-on-7 drill, Cook came from across the field to make a leaping interception of a Josh Johnson pass intended for Brandon Lloyd.
It was unclear whether Lloyd located the pass as it was in the air. In any event, he did not offer any resistance on the play, 49ers defensive coordinator Vic Fangio noted.
"But the fact remains, he did go up and get it,” Fangio said. “That’s always a good thing.”
Here are some other notes and observations as the 49ers returned to practice after a day off:
--Rookie receiver Bruce Ellington suited up for his first practice after opening training camp on the non-football injury list. He saw some work but did not catch any passes in team drills. Ellington was also deep, working on fielding punts. He bobbled one punt, but appeared to handle the other flawlessly.
--LaMichael James, who sustained a dislocated elbow on Sunday, was seen without a brace on either arm. Initially believed he dislocated his left elbow, James’ right elbow appeared to be twice the size of his left.
--Tight end Vance McDonald got off to a good start with nice one-on-one pass blocking against Ahmad Brooks and Dan Skuta. In 7-on-7, McDonald made a nice catch 25 yards down the field on a bullet from Colin Kaepernick against the coverage of safety Antoine Bethea.
--In a one-on-one drill in the red zone, receiver David Reed made a sensational diving catch of a Blaine Gabbert pass against the coverage of rookie Kenneth Acker.
--Colin Kaepernick hooked up with Michael Crabtree on a 19-yard post pattern for a touchdown against Perrish Cox.
[MAIOCCO: Kaepernick says Crabtree 'a step or two quicker']
--Lloyd’s short touchdown catch against rookie Dontae Johnson was waved off due to pass interference.
--The 49ers had some mix-ups on defense, including a play in which Crabtree caught a 35-yard touchdown pass from Kaepernick. Crabtree was left all alone on a blown coverage on a blitz.
--Outside linebacker Aldon Smith continued to look unblockable during team drills.
--During a third-down drill, the defense stopped the offense 8-of-10 times. One conversion came on a quick count when Gabbert recognized nobody was covering Quinton Patton.
--Inside linebacker Chris Borland had an interception on a deflected pass.
[RELATED: Fangio: Borland's instincts have gotten him into trouble]
Daily transactions: Signed RB Alfonso Smith; claimed T Michael Philipp off waivers from Dolphins; waived QB Kory Faulker; waived/injured G Fouimalo Fonoti.
Returned to practice: WR Bruce Ellington (ankle)
Did not practice: RB LaMichael James (dislocated elbow), RB Kendall Hunter (torn right ACL), CB Tramaine Brock (ankle), CB Chris Culliver (leg), DL Justin Smith (offseason shoulder surgery), DL Ray McDonald (leg), RT Anthony Davis (offseason shoulder surgery), C Marcus Martin (ankle), LB Aaron Lynch (hamstring).
Physically unable to perform: LB NaVorro Bowman (knee), NT Ian Williams (lower leg), TE Garrett Celek (back), Kaleb Ramsey (NA).
Non-football injury: RB Marcus Lattimore (knee/hamstring), FB Trey Millard (knee), CB Keith Reaser (knee) and G Brandon Thomas (knee).
Reserve/did not report: RG Alex Boone (contract holdout).