Calf strain rules Mako Vunipola out of England's autumn internationals
Mako Vunipola will miss England's entire autumn internationals series with a calf strain, deepening boss Eddie Jones' front-row injury crisis.
Saracens' loosehead prop will be sidelined for six weeks, with lock Nick Isiekwe also ruled out for two months due to an ankle concern - taking England's contingent already confirmed to miss the autumn series to 16 players.
Mako Vunipola becomes England's fourth loosehead missing ahead of the autumn: Joe Marler has retired from Test rugby, while Leicester's Ellis Genge, Bath's Beno Obano and Wasps' Matt Mullan are all sidelined with long-term knee trouble.
"Mako's got a calf injury, so it looks like it's going to be around six weeks," said Saracens' rugby director Mark McCall. "It's a tear in his calf, it doesn't require surgery.
"Nick (Isiekwe) will be around eight weeks, it's a syndesmosis injury of his ankle.
"That doesn't require surgery either, and it will be eight weeks."
Head coach Jones will therefore have to hand someone a full debut in the first autumn Test, against South Africa at Twickenham on Saturday, November 3.
Exeter Chiefs' Alec Hepburn has one cap as a replacement, while his club-mate Ben Moon and Gloucester's Val Rapava Ruskin will now be England's other main options at loosehead prop.
Nathan Hughes could yet become another casualty for England's autumn, with the Wasps number eight facing a reconvened disciplinary hearing on Tuesday night.
But Mako Vunipola and Isiekwe join Genge, Obano, Mullan, Joe Launchbury, Jonny Hill, Billy Vunipola, Sam Simmonds, Jack Willis and Chris Robshaw as England's sidelined forwards.
Dan Robson, Jonathan Joseph, Anthony Watson and Marland Yarde are all missing from the back-line, with Ben Te'o still a doubt despite working his way back to fitness.