The Washington Redskins learned on Monday that they will be without starting strong safety Duke Ihenacho for at least six to eight weeks because the fourth-year veteran needs surgery to repair a fractured and dislocated left wrist, Coach Jay Gruden said.

Meanwhile, the team will have to go without starting wide receiver DeSean Jackson for roughly three to four weeks as he heals from a strained hamstring.

Ihenacho suffered his injury in the second quarter and didn’t return. He had three tackles.

The MRI exam conducted on Ihenacho’s wrist on Monday confirmed the damage. Gruden said the team hasn’t yet decided whether or not to place Ihenacho on injured reserve.

This offseason, Ihenacho competed with free agent signing Jeron Johnson for the starting strong safety job. The two alternated days working with the first team. Ihenacho pulled away from Johnson during the preseason when Johnson missed some time with a strained hamstring.

However, Johnson who in the spring signed a two-year, $2.5 million deal with $350,000 of it guaranteed wasn’t the first option once Ihenacho got hurt.

Backup free safety Trenton Robinson took over and finished the game with eight tackles.

It wasn’t immediately clear if Robinson would take over as the starter, or if Johnson or rookie Kyshoen Jarrett would receive consideration.

Meanwhile, coaches also must come up with a contingency plan at wide receiver opposite Pierre Garcon.

Jackson, who missed all of the preseason with a sprained AC joint in his left shoulder, hurt his hamstring on the first play of the Redskins’ second possession. Kirk Cousins attempted a deep throw to Jackson up the right sideline, but Jackson injured his hamstring while trying to track down the ball. He said he felt the pull, and he ended up being overthrown. Jackson left the game and didn’t return.

The injury to Jackson robs Washington of its most explosive weapon.

Jackson last season led the offense with 1,169 receiving yards and six touchdowns on 56 receptions. His 4.35-second 40-yard dash speed makes him a challenge for most cornerbacks to cover him one-on-one.

Without Jackson, Washington didn’t take any shots downfield, and Gruden said his absence forced him to scrap seven deep routes from the game plan on Sunday.

Second-year pro Ryan Grant replaced Jackson in the lineup, but he doesn’t possess the same blazing speed.

It’s possible that preseason star Rashad Ross, who was inactive for the opener, could serve as the team’s top deep threat in the interim.

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