Jon Gruden has a career record of 95-81 (.540) with nine playoff appearances and one Super Bowl victory in 11 seasons as a coach. (Kirby Lee/USA TODAY Sports)

Jon Gruden was welcomed back for a second stint as Oakland Raiders coach on Tuesday, now he’ll be tasked with getting them back to the postseason. Based on his starting point, however, an immediate return to the playoffs is unlikely in 2018.

To be competitive with the Kansas City Chiefs (10-6) and Los Angeles Chargers (9-7), the Raiders would have to win at least four more games than they did in 2017, which will be difficult considering their net point differential was five points per game worse than expected after accounting for the down, distance and field position of each play for and against. The Chiefs and Chargers, by comparison, were 2.3 and 8.7 net points per game better than expected.

Yes, both teams will undergo offseason changes, as will the Raiders. But the broader recent history of the league shows there is significance to that five-point gap. Among the 112 teams that were as bad or worse than the Raiders were in terms of net expected points since 2002, the first year the league expanded to 32 teams, only three — the 2003 San Diego Chargers, 2007 Baltimore Ravens and 2011 Denver Broncos — were able to get that number to a point that would compete with a divisional winner (eight or above).

So where can Gruden make up ground and quickly improve this roster? The wide receivers — once thought to be a strength of this team — may need a makeover.

According to PFF, Oakland’s pass catchers were the third-worst in the NFL last season, behind only the New York Giants — who saw star Odell Beckham Jr. suffer a season-ending injury early in the season — and the Buffalo Bills. The team’s top wideout, Michael Crabtree, averaged 1.6 yards per route run in 2017, placing him 29th out of 45 qualified players at the position.

Amari Cooper produced even fewer yards per route run than Crabtree (1.5), and was ranked 60th out of 78 qualified receivers for his on-field performance. Both need to be better in 2018. If not, Gruden is going to have to find Carr a top target to throw to.

Gruden has even more work cut out for him on the defensive side of the ball. Oakland allowed 2.1 points per drive last season, the fourth-most in the league, with a 101.8 passer rating against, the third-worst in football in 2017. To put that in perspective, opposing quarterbacks performed as well as Carson Wentz — an MVP candidate before his season-ending injury in Week 14 — against the Raiders while the league average was closer to that of Andy Dalton (86.6).

Oakland’s top priority, therefore, must be a shut down corner.

Sean Smith turned in a decent effort for the Raiders in 2017 with a team-leading two interceptions, but opposing passers still produced a 94.7 rating against him in coverage. Dexter McDonald and T.J. Carrie were even worse, allowing passer ratings of 102.3 and 108.1 in coverage during the regular season. Alex Smith’s 104.7 passer rating led the league,further illustrating just how bad Oakland’s secondary was by the end of the season.

To be fair, Gareon Conley and David Amerson both saw their seasons shortened by injury, but it is doubtful a rookie (Conley) and the 104th best cover corner (Amerson), would have made much difference.

There is reason to believe that Oakland — a 12-win team in 2016 — underperformed drastically this past season and could be capable of a much better record than they earned. And maybe Gruden has learned enough to make the leap as fast as one of those three teams. But it’s more likely than not the Raiders will have to wait a year or two before they are good enough to become a playoff contender.

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