Dylan Hartley will be available for England's entire RBS 6 Nations campaign after being given a six-week ban for striking Sean O'Brien.
Hartley appeared before an independent disciplinary hearing in London to be sanctioned for the third red card of his career, received in Northampton's Champions Cup defeat by Leinster on Friday.
The length of the suspension means he is free to play from January 23, enabling him to lead England when they open their Six Nations defence against France at Twickenham on February 4.
Hartley had only been on the pitch for six minutes as a second-half replacement when he struck O'Brien with a swinging right arm from behind, resulting in the Ireland flanker failing a head injury assessment.
The thee-man hearing upheld the decision of referee Jerome Garces to issue a red card and found that the offence was at the mid-range of World Rugby's sanctions, selecting a five-week suspension for the offence.
Two weeks were added due to Hartley's poor disciplinary record before it was reduced by one week because of his guilty plea.
Before this latest red card, Hartley had amassed 54 weeks work of suspensions for offences including biting, gouging and butting and the total for his chequered career now stands at 60 weeks.
It is the best possible outcome England could have wished for, realising a substantial lay-off was certain but now able to plan for the Six Nations knowing the skipper for all 13 victories this year will be at the helm right from the start.
The Rugby Football Union outlined its positions on Tuesday, stating that Hartley had the full backing of Twickenham and head coach Eddie Jones regardless of the outcome of the hearing.
"I think Dylan's got credit in the bank," RFU chief executive Ian Ritchie said.
"I think most people would say it's been a fantastic year. We've had 13 wins out of 13 and Dylan has made a huge contribution and he should be allowed to continue that.
"Dylan has clearly played a fantastic part in captaining the team, on and off the pitch just to be clear. His leadership credentials are very strong. He's made a huge contribution.
"So you view all these things in perspective and in perspective one looks at the totality of what he's done and what's happened over the years. I think we should be supportive of that."
Hartley had been a leading contender to lead the British and Irish Lions tour to New Zealand next summer, only for his odds to lengthen upon his dismissal at Franklin's Gardens.
Former Lions skipper Brian O'Driscoll suggested his swinging arm had ended any captaincy aspirations, but head coach Warren Gatland insists he remains a possibility.
"Absolutely not, I don't think it's about ruling anyone out - it's so early to be thinking that far ahead," Gatland said.
"There are a number of people who will be in contention for a potential captain's role. But it is about picking the squad first. There is a lot of water to go under the bridge before those sort of things are finalised.
"To be fair to Dylan, in the last 12 months he has had a great track record and you have to feel for him.
"Hopefully he will take his punishment and get back for the Six Nations and hope he goes well."