The 20-year-old, capped three times for Ireland, played 18 times for the Irish region in the RaboDirect PRO12 this season as they claimed a tenth-place finish.
Henshaw, who made his debut for Connacht in September 2012, emerged as one of the standout performers at outside centre with his competitive nature catching Lam's eye.
And comparing Henshaw's desire to that of one of world rugby's most successful and influential players in Jonny Wilkinson, Lam insists the future could be particularly bright.
"The first thing is he has got some talent," Lam told the Irish Independent. "No doubt he has the physique, but the thing that sets him apart is that he has got is the competitive nature and the desire.
"I played with Jonny Wilkinson when he was 18 and he used to struggle when we'd lose games, he was so driven. There are a lot of similarities with Robbie, he's a competitor.
"There is no doubt that, at 20, there is a lot of learning still to go and develop in his game.
"Defensively he is very strong, but if you look at all the best centres in the world - centre and No.8 are
experienced positions and you get better and better.
"Some of the things that he is doing at his age defy the years, but he'll just get better and better."
To get your hands on tickets for the RaboDirect PRO12 final, visit http://www.rabodirectpro12.com/final/tickets.php
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