England ran in six tries in all at Twickenham including one from Willis before he was stretchered off after being rolled away from the collision area by Sebastian Negri.
Jones said: “I always leave those things to the referee. The referee has to make a decision on whether that’s right or not.”
As for the latest blow sustained by Willis, who has been the victim of a catalogue of injuries, Jones added: “We’re all concerned. He’s on crutches, he’ll be examined tomorrow but obviously it didn’t look good. We’ll just wait and see. He’s got some sort of knee injury and he’s been back in the dressing room with us.”
Farrell, meanwhile, backed Willis to “come back better” from the injury, which looks likely to result in a lengthy spell on the sidelines for the back-row forward, who was making his Six Nations debut off the bench against Italy.
England fell a try behind after just three minutes on Saturday but Jones insisted it gave England the required jolt a week on from being totally outclassed by Scotland.
“We were a bit slow in the game”, he said. “I wasn’t too perturbed. I thought it had a positive effect on us.”
But Jones said England needed to make a marked improvement to pick up their second win of this year’s Six Nations against Wales in Cardiff on February 27.
He added: “We’ve got to get better set-piece dominance. We haven’t been able to exert enough consistent pressure through the scrum or our lineout. They’d be the two areas.”
QBE Insurance helps businesses build resilience through risk management and insurance. For more information, go to QBEeurope.com