Northampton backs Luther Burrell and Stephen Myler have been added to the England squad for the tour of South America after Alex Goode and Joel Tomkins were ruled out through injury.
Goode and Tomkins have been sidelined by shoulder and ankle injuries respectively and will miss Sunday's clash with the Barbarians at Twickenham and the trip to Uruguay and Argentina.
Uncapped pair Burrell and Myler will join up with the national squad after Saturday's Premiership final against Leicester.
"Luther and Stephen have played well in the second half of the season and have a great opportunity to put a marker down for the future on this tour," said England head coach Stuart Lancaster.
"Our commiserations go to Alex Goode and Joel Tomkins.
"It's disappointing that they have to miss out but they've had excellent seasons and I'm sure they'll be back in contention next season."
Nine of the squad are appearing in Saturday's final between Leicester and Northampton, so Lancaster has called up Exeter scrum-half Haydn Thomas and Sale lock Kearnan Myall to assist in the build-up to the Barbarians.
"It's good to have Haydn and Kearnan involved in the senior England environment ahead of what should be a great game against a very strong Barbarians team," added Lancaster.
"They have both played well recently and deserve this opportunity."
England will face a CONSUR XV in Montevideo, Uruguay on 2 June, followed by Tests against Argentina in Salta on 8 June and Buenos Aires seven days later.
Starting full-back for the Lions?