England have been handed a timely injury boost ahead of their daunting Six Nations opener against Ireland, with Alex Mitchell now back in camp.

The Northampton scrum-half was added to Steve Borthwick’s 36-man training squad on Monday, having sat out the entire autumn international series with a neck injury.

Mitchell also suffered a knee issue during Saints’ thrilling Champions Cup win over Munster earlier in January, but has now joined up with England in a much-needed boost ahead of Saturday’s trip to Dublin.

The 27-year-old has established himself as Borthwick’s first-choice No9, with Ben Spencer and later Jack van Poortvliet filling in during the autumn.

Spencer is also now in the squad for the upcoming Six Nations, with Bristol’s Harry Randall and Sale’s Raffi Quirke adding extra scrum-half cover and Van Poortvliet missing the Ireland game through injury.

Mitchell is expected to be partnered at half-back at the Aviva Stadium by Marcus Smith, who is set to hold off competition from namesake Fin Smith to retain the No10 shirt.

Freddie Steward looks poised to get the nod at full-back, with George Furbank sidelined after fracturing his arm while playing for Northampton in the Champions Cup against The Bulls last month.

The Telegraph reported on Tuesday morning that England were considering playing both Curry twins, Tom and Ben, in their back row against reigning champions Ireland along with Ben Earl, plus naming a bench containing six forwards and only two backs.

England were hit by a flurry of fitness setbacks ahead of their latest Six Nations campaign, with hooker and vice-captain Jamie George - replaced as skipper after only 12 months by lock Maro Itoje - ruled out of the Ireland match with a hamstring injury sustained playing for Saracens against Castres.

Harlequins No8 Alex Dombrandt and Northampton lock Alex Coles are also out, leading to the likes of Spencer, Quirke, Curtis Langdon, Arthur Clark and Henry Pollock being added to the squad who have been preparing for the tournament with a training camp in Girona.

Mitchell’s return has led to Northampton team-mate Pollock being left out ahead of the trip to Ireland, with Borthwick expected to name his starting team on Thursday.