As a former star running back for Oklahoma, Adrian Peterson knows what the Sooners are capable of on a yearly basis.

Before he embarked on his NFL career with the Minnesota Vikings (2007-16) and three teams since then, joining the Washington Redskins for the past two seasons after spending 2017 as a member of the Arizona Cardinals and New Orleans Saints, Peterson was an offensive weapon for Oklahoma.

Having watched the Sooners into the 2019 campaign, Peterson was optimistic but realistic about the team's outlook when asked Saturday by FOX college football analyst Reggie Bush.

"I feel like we can (run the table)," Peterson said. "What I'm looking for (is improvement) defensively — because the offense, we can put points on the board. Outside of that, if our defense can stay strong and the secondary and our front, we can run the table."

Peterson was measured when he issued his take on Oklahoma (4-0, 1-0), which has posted high-flying numbers on offense once again under third-year head coach Lincoln Riley but faced struggles with defense over the past two years.

The Sooners' offseason hire of first-year defensive coordinator Alex Grinch has led to largely positive returns early on.

Through four games, Oklahoma has given up an average of 18.8 points each time out — tied for 29th nationally — with Week 1's Sept. 1 opener against Houston, a 49-31 win, the lone hiccup.

In subsequent victories against South Dakota (70-14, Sept. 7), UCLA (48-14, Sept. 14) and Texas Tech (55-16, last Saturday), the Sooners have outscored opponents by a combined margin of 173-44 — averaging 14.7 points allowed with each outing.

Who better to catch up with before an @OU_Football game than @AdrianPeterson?@ReggieBush chats with the Sooner legend about Jalen Hurts and Oklahoma's chances of making the CFP ?? pic.twitter.com/7txqLtEXa7 — FOX College Football (@CFBONFOX) September 28, 2019

On the other side of the ball, Jalen Hurts has been Oklahoma's offensive catalyst, replacing 2018 Heisman Trophy-winning quarterback Kyler Murray and blazing his own trail to the award.

Through four games, he has completed 66 of 85 passes (77.7 percent) for 1,295 yards and 12 touchdowns to one interception while adding 47 rushes for 443 yards (9.4 average) and five touchdowns.

"I think he has as good a chance as anybody else that's out there," Peterson said of the Alabama graduate transfer's shot to win the Heisman. "And the type of season he's having is amazing."

Hurts can add on his eye-popping numbers when Week 6's Saturday game against Kansas (2-3, 0-2) — a noon ET kickoff on ABC — at David Booth Kansas Memorial Stadium in Lawrence.

The Sooners under Riley — the successor after former head coach Bob Stoops (1999-2016), who recruited and mentored Peterson (2004-06) prior to stepping down almost a decade later in June 2017 — have impressed on offense.

Before Hurts and Murray lit up stat sheets, quarterback Baker Mayfield did the same and won the 2017 Heisman.

The game has changed since Peterson declared for the 2007 NFL draft, where he jumped into his seven-time Pro Bowl career as the Vikings' first-round pick at No. 7 overall.

While at Oklahoma, Peterson was the offense's workhorse. He took 748 carries for 4,041 yards (5.4 average) and 41 touchdowns while adding 24 receptions for 198 yards (8.3 average) and a touchdown. During his three seasons with the Sooners, the team went 31-8 overall.