If we had this conversation before March 10th, statically speaking, Pagan looked like a much better player to fill in for Alou. However, over the past week, from the 10th to today, our conversation would be very different. Over the past week, against all teams, starters have been getting more playing time, and this is when roster moves are finalized. A player can hit up minor leaguers all he wants, but what he does against the major league caliber is what can make or break that player.
Throughout spring, Pagan's BA has been .351 and OBP has been .373. His BA is amazing. Clark on the other hand, thanks to his past week, is riding a hot streak that has raised his BA to .302 and his OBP to .412.
Specifically over the past week:
Clark 7-16, 3BB, .438 BA, .526 OBP
Pagan 5-22, .227 BA, .227 OBP
Pagan has hit a slump, and Clark has hit a hot streak. That spot on the bench has never been Pagan's or Clark's but this past week brings both of them up on an even playing field. Personally, what I think will happen is close to the start of the season, when Alou's condition is better known, he will be placed on the DL for the right amount of time and both Clark and Pagan will make the roster. Then it becomes a continued competition for who stays and who goes when Alou gets back.
On top of all of this, do not count Endy out for the platoon out if he is healthy enough by the start of the season.
