Is that fair? Helton did lead the Trojans to the Rose Bowl in 2017 and Cotton Bowl in 2018, and most of that was with the help of first-round pick Sam Darnold. With the right quarterback, Helton could be in business.MORE: Pac-12 2019 early conference primerThat said, USC cannot have the sixth-ranked coach in the conference and expect to compete for national championships. The rest of the field is improving too. Mel Tucker joins that group with his first year in Colorado.With that in mind, here is a look at our Pac-12 coach rankings: 2019 Pac-12 Coach Rankings RankNameSchoolWLPCT.OVR1Chris PetersenWashington13933.80862David ShawStanford8226.759113Mike LeachWashington State13383.616174Kyle WhittinghamUtah12061.663215Chip KellyUCLA4916.754296Clay HeltonUSC3217.653317Mario CristobalOregon3652.409438Herm EdwardsArizona State76.538449Kevin SumlinArizona9150.6456010Justin WilcoxCal1213.4806411Jonathan SmithOregon State210.1677212Mel TuckerColorado00.00078MORE: SN’s post-spring preseason top 25Quick reads — Washington’s Chris Petersen is the only top-10 coach in this year’s ranking. He has the highest winning percentage among coaches with at least 100 victories, at .808. Sporting News’ annual 1-130 coach rankings are here. Today, we’ll dig a little deeper into our Pac-12 coach rankings. USC’s Clay Helton is the coach in focus after a 5-7 season knocked him out of the top 25 in our overall rankings. Helton has a remodeled coaching staff and a ton of pressure heading into the 2019 season. — Chip Kelly had a 10-spot drop in the overall rankings after a 3-9 record in his first season at UCLA. Kelly still has coached in a national championship game this decade. He could easily jump back up.— David Shaw and Mike Leach also have winning percentages of better than .700 over the last three seasons. The Cardinal won the conference championship in 2015. Leach is still looking for that breakthrough with the Cougars.— Among returning coaches, Arizona State’s Herm Edwards jumped 43 spots from last year’s overall rankings for the biggest gain. Arizona’s Kevin Sumlin had a 22-spot fall for the biggest drop.