ANNE M. PETERSON, AP Sports Writer

EUGENE, Ore. (AP) — Oregon’s defense needs to quickly address season-opening missteps with the much-anticipated visit to No. 5 Michigan State looming on Saturday.

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The seventh-ranked Ducks defeated Eastern Washington 61-42, and in addition to those six touchdowns, the Big Sky’s Eagles amassed 549 total yards.

Afterward, defensive coordinator Don Pellum said pointedly: “Overall it’s just not where it needs to be. I think we know that. I think everyone knows that.”

The Ducks’ vulnerability came mostly against the pass. Eastern Washington’s starting quarterback Jordan West and backup Reilly Hennessey threw for a combined 438 yards. Receiver Cooper Kupp caught 15 passes for 246 yards — both Autzen Stadium records — and three touchdowns.

Oregon’s secondary lost three starters from last season when the Ducks went 13-2 and to the championship game of college football’s first playoffs.

Three of Oregon’s starters at defensive back from last season have moved on: Ifo Ekpre-Olomu, Erick Dargan and Troy Hill. Sophomores Chris Seisay and Arrion Springs started at corner for the Ducks against Eastern Washington. At safety, sophomore Tyree Robinson made his second career start. Junior safety Reggie Daniels is the only returning starter in the secondary.

“We didn’t do a ton defensively, but what we did — obviously you want to do it cleanly and do it well,” Helfrich said. “We had some first-time guys back there trying to peek on the backfield or peek on somebody that’s not their assignment or a fit that’s not their job. And they just need to tackle better.”

The passing yards were the most Oregon had allowed since the 2013 season. Eastern Washington was 6-for-6 within the 20-yard line.

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Last year Michigan State was ranked No. 7 when the team came to Autzen Stadium and the Marcus Mariota-led Ducks rallied from a third-quarter deficit for a 46-27 victory. Connor Cook threw for 343 yards and two touchdowns for the Spartans but the then-No. 3 Ducks scored four straight touchdowns to close out the victory.

Michigan State had issues of its own in its 37-24 victory over Western Michigan on Friday night.

Western Michigan’s Zach Terrell threw for 365 yards, the most passing allowed by the Spartans since a game against Notre Dame five years ago. Corey Davis caught 10 passes for 154 yards and a touchdown and Daniel Braverman caught 13 passes for 109 yards.

According to STATS, the Spartans hadn’t allowed two opponents to have 100 yards receiving in a regular season game since 2009 against Northwestern.

Michigan State was paced by Cook’s 256 yards passing and two touchdowns. Aaron Burbridge had four receptions for 117 yards and three Spartan running backs combined for 190 yards rushing on 35 carries.

Oregon was boosted in its opener Saturday by new quarterback Vernon Adams, taking over for Mariota. Adams, who transferred to Eugene from Eastern Washington for his final season of eligibility, threw for 246 yards and two touchdowns. Sophomore running back Royce Freeman ran for a career-high 180 yards and three scores.

“Solid,” Helfrich said of Adams’ performance. “He did some good things.”

Saturday will mark the first time two top 10 teams have met in Spartan Stadium since 1966, when No. 1 Notre Dame played No. 2 Michigan State to a 10-10 tie.

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