Jimenez is a non-roster invitee. He is getting the playing time at SS while Young is with the USA team. Jimenez is 6 for 20 with a double and 2 runs scored.
It would be a mistake to hold a young prospect back or even bench him in favor for Derosa. It is still early...Right now they are getting the same amount of time at 2B. DeRosa is currently 1 for 13. Kinsler has a single, double, 1 SB, 3 BB, 1 K and a HR and 5 runs in 11 abs. Not a bad start to spring.
Here are kinsler's minor league numbers.
http://thebaseballcube.com/players/K/ian-kinsler.shtml
I'd expect 400 ab's as a minimum. Kinsler is 23 yrs old so they will push for 500 and if it is not working out he will be back in AAA. I can't imagine a guy like him watching much from the bench. I think it is going to work out.