Joe Marler
England and Harlequins prop Joe Marler has been no stranger to controversy over recent monthsSteve Bardens/Getty Images for Harlequins

Joe Marler has been issued with a formal warning by the Rugby Football Union (RFU) following his obscene social media insult directed at Bob Dwyer. The former Australia coach, who guided the Wallabies to their first World Cup triumph in 1991 and later took charge of Leicester Tigers and Bristol, was labelled a w****r by England's absent prop on Twitter earlier this week after his strong criticism of Dan Cole's perceived illegal scrummaging during the first Test in Brisbane. The post was later deleted.

Harlequins loose-head Marler did not travel with the Six Nations Grand Slam winners for their three-match summer tour, instead choosing to rest and recharge his batteries after a "very enjoyable but sometimes difficult season" in which he attracted no shortage of controversy. The 25-year-old was eventually handed a two-game suspension and a £20,000 ($28,251) fine by World Rugby for calling Wales prop Samson Lee a "gypsy boy" at Twickenham in March. He was later banned for another two weeks for kicking Grenoble forward Arnaud Heguy during April's European Challenge Cup semi-final.

"The RFU can confirm Joe Marler has been issued with a formal warning under RFU regulation 19.6.14, following his comments made on social media about former Wallaby coach Bob Dwyer on Tuesday 14 June," English rugby union's governing body confirmed in an official statement.

"Marler is extremely apologetic for the comment that was made and deleted it within a few minutes of it being posted on Twitter. The warning will be retained on Marler's disciplinary record for a period of five years and may be relied upon in any future disciplinary proceedings. The RFU considers this matter closed and will not be commenting further."

England secured only their fourth ever victory down under last weekend as the reliable boot of Owen Farrell and tries from Jonathan Joseph, Marland Yarde and Jack Nowell set the seal on a nervy 39-28 triumph at Suncorp Stadium, yet both Dwyer and former Wallaby hooker Phil Kearns chose to slam their approach at the set piece.

"How anyone could have allowed Dan Cole to scrummage the way he did was absolutely beyond me," Dwyer, who has previously criticised Marler, said according to the Sydney Morning Herald. "How two assistant referees and one referee on the pitch could allow him to consistently and blatantly break the laws of the game, I'm not sure. I couldn't say that Dan Cole's experience and ability didn't play a big part in his clear points win over Scott Sio, but we do expect some semblance of accuracy in accordance with the laws of the game.

"On one occasion, in particular, Cole's backside was out of the scrum facing one sideline and his head was in the scrum facing the other sideline. His most consistent offence was angling in but on other occasions he managed to roll his right shoulder and give nothing to push against, causing Scott Sio to roll in as well. More times than not it was a penalty [against Australia]. People will say it's sour grapes and I don't mind that but before they do I hope they have a good look at the video of the game and make their judgement on the facts."

The second Test between England and Australia takes place in Melbourne on Saturday (18 June). Eddie Jones has opted to draft in George Ford at fly-half, with Farrell switching to inside centre in place of Luther Burrell. Nowell has also been selected ahead of Yarde, who drops out of the squad altogether. Jamie George, Jack Clifford and Elliot Daly have all been included as replacements, while former skipper Chris Robshaw wins his 50th cap.