Rams left tackle Greg Robinson must deliver against the Cardinals

Rams who must deliver…

Left tackle Greg Robinson. The third-year pro will be equally important protecting quarterback Case Keenum’s blindside and helping to clear the way for running back Todd Gurley. Keenum has been sacked six times in three games. Gurley has yet to break out with a big performance, but University of Phoenix Stadium is where he did it as a rookie.

Defensive end Robert Quinn. He doesn’t have to save the victory with another last-second tackle, but Quinn and his teammates along the line must pressure quarterback Carson Palmer and take some of the pressure off a secondary charged with containing one of the NFL’s deepest receiver corps.

Cornerback Trumaine Johnson. Palmer will no doubt go after cornerback Troy Hill, but it is imperative that Johnson remains aggressive against a receiving corps that features multiple playmakers. Johnson helped the Rams come up with an interception last week when he hit a Tampa Bay receiver and caused the ball to ricochet into the hands of linebacker Mark Barron.

Cardinals to watch for…

Receiver Larry Fitzgerald. The veteran wideout is so athletic, Rams defensive coordinator Gregg Williams says it’s like Fitzgerald “plays basketball” on a grass football field. The nine-time Pro Bowl selection has 20 receptions, including three for touchdowns. Rams cornerbacks Trumaine Johnson and Troy Hill said they were looking forward to the challenge.

Linebacker Chandler Jones. He had 12½ sacks last season playing defensive end for the New England Patriots and he already has three for the Cardinals. Jones has 39 sacks in four-plus NFL seasons. Fellow linebacker Markus Golden also has three sacks for a defense that features linebackers Deone Bucannon and Kevin Minter and ends Calais Campbell. USC product Frostee Rucker has been declared out (knee).

Cornerback Patrick Peterson. One of the top cornerbacks in the NFL, Peterson can influence or change an offensive game plan. The former Louisiana State star has made the Pro Bowl in each of his five seasons. He has intercepted two passes this season.

gary.klein@latimes.com

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