Saracens forward coach Alex Sanderson has backed Mako Vunipola to continue his "meteoric rise" next season.
Vunipola was one of three loosehead props intially selected for the British and Irish Lions tour to Australia, going on to start the second Test following injuries to Gethin Jenkins, Cian Healy and Alex Corbisiero.
The England loosehead struggled at the set-piece in Melbourne but has been backed by Sanderson to carrying on his impressive development next season, having benefited greatly from the experience of touring with the Lions in a whirlwind season.
"I'm so proud of him and what he has achieved, it really has been a meteoric rise," said Sanderson to The Rugby Paper.
"I feel Mako was a bit hard-done by in that second Test. He made more tackles than any other Lions player. The work-rate that he puts in is comparable to a back-rower.
"The injuries the Lions have had at prop mean that Mako has taken on a lot of responsibility, possibly more than they anticipated.
"But he played the whole game in that second Test and by the end he was winning penalties not losing them like he was in the first half.
"That was against some of the best scrummagers in the world. The idea that the Australian set-piece is weak is a bit of a myth, they're some of the best out there who have the experience of playing with each other.
"At Mako's age he is improving all the time. He will come back from this Lions series with so much experience, look how he turned it around in that match. He was possibly a bit found out for 20 minutes and he learned. He will be one of the best in the world before long, there's no doubt about that in my mind.
"Look at where he was last season to where he is now. His scrummaging has come on so much that last season he was dominating people on the European stage.
"The scrum is a kinaesthetic learning process - you have to be in it and feel it if you want to improve. There's only so much you can learn looking at videos and on the machine, the rest you have to learn out on the pitch.
"That's why being a few years older and having that bit more experience is so important as a prop."