They can prevail if if they have equal numbers and the combat is done on horseback but if it is infantry based combat and fighting is done on land, Rajputs or for that matter anyone will be thrashed by romans, Roman legions were invincible on three accountsThis comparison is not very fruitful as I've learned.
Basically, both the powers belong to very different geographies, timelines and military technologies.
Comparing them won't do any good.
For argument sake, I'd say Rajputs strength was close combat after galloping with a frontal cavalry charge.
They're likely to prevail in close combat only.
Regards,
Virendra
1. Superior training
2. Central organizational advantages like defeat of tens of thousands of warriors was easily replenished due to great organization of roman army
3. Physique and tactics were core of their strength. No one less than 5 feet 10 inches was recruited and the discipline exhibited by the romans can be seen at battle of Carrhea where they lost heavily but initially even cavalry of Parthians( the predecessor of turk cavalry which was so dreadful for us) failed to break their ranks despite furious onslaughts.
It was only the retreat tactic which led to thrashing of romans. Rajputs stand no chance even with their cavalry as I do not think rajput cavalry was as heavy as persians and persians too had a hard time in breaking ranks of romans.
However, elephants and archers could play a role but these are not traditional rajput strength but the mainstay of clasical ancient indian kshatriyas. If Skandagupta could defeat hunas, it was through his longbow type archers armed with bows over 6 feet. If you employ them against Roman in thousands and in case of their attack shower them with arrows, it may be useful but alas rajputs did not possess archers in tens of thousands and so I think they have little chance against Romans.