Since last week, we’ve been examining the strongest and weakest positions on each Big 12 roster as teams enter summer workouts.

The series continues with the Oklahoma State Cowboys.

With first-team All-Big 12 receiver James Washington returning, Oklahoma State's passing game is expected to be among the nation's elite in 2017. Kevin Jairaj/USA TODAY Sports

Strongest position: Wide receiver

No doubt about it, the Cowboys’ receivers rank as the best group in the Big 12 and possibly the best in the country, featuring depth, skill and experience. It helps that Mason Rudolph, a career 62.3 percent passer, delivers the ball, but James Washington, Jalen McCleskey and the cast of many stand alone as a top-flight group.

Washington returns as a senior and a Biletnikoff Award favorite after earning first-team All-Big 12 recognition for his 1,380 yards and 10 touchdowns on 71 catches. Washington’s 28 receiving touchdowns rank as the most by an active FBS player to enter 2017.

McCleskey, a 5-foot-10 speedster, caught two more passes than Washington last year and hauled in seven touchdowns.

Marcell Ateman, who redshirted because of injury last season, was a mainstay in the lineup for the previous three seasons. He adds size at 6-4 alongside 6-3 Chris Lacy, who caught 31 passes in 2016.

The addition of Tyron Johnson, though, pushes this unit over the top. He starred in the spring in preparation for his debut with the Cowboys after playing 2015 as a true freshman at LSU. Johnson is a known commodity, ranking as the No. 30 prospect nationally out of New Orleans among recruits two years ago.

Weakest position: Defensive back

Oklahoma State doesn’t have a weak spot to enter 2017. Hence, its position at No. 6 in the latest Way-Too-Early Top 25.The secondary, with several questions to answer, sits as perhaps the lone position group without a secure spot in the top half of the Big 12.

Gone are three of the top four cornerbacks -- and the other, Ramon Richards, moved inside this spring to play safety, where the Cowboys must replace standout Jordan Burton.

Oklahoma State is relying on A.J. Green and Clemson graduate transfer Adrian Baker to man the corner positions, but it will need more than two strong defenders in coverage to handle the high-flying Big 12.

Tre Flowers remains entrenched at safety.

The Cowboys did not surrender 300 yards through the air in defeat last year. This group may find difficulty in duplicating their success. But if it happens, look for Oklahoma State in the College Football Playoff chase.