However, a Jack Dixon try along with James Benjamin's late double gave Dragons their fourth GUINNESS PRO12 win in a row.
"Of all the games we have had we knew this was going to be so tough and so testing," Jones told Wales Online.
"We knew Leinster were coming here not just for the win, but to score four tries and to get a bonus point.
"They played very well in the first half and we knew, if we weren't going to score 23 points, we wouldn't win.
"But we worked hard and came back strongly and, hey, we got a bonus point as well. Unbelievable!
"We are getting the basics right and we know what we need to improve on. It wasn't easy, we lost flanker Nick Crosswell (back) and lock Cory Hill (head) to injury just after half-time but the boys who came on were outstanding.
"They are just so young, a bunch of kids. You can see the mistakes they are making in games but you have got to give them time and space to grow."
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