The core of the team changed with the 2011 trade with the Dodgers. A changing core is not the reason for the frustrating performance in April. Bigger changes to the core were made last year when we fielded a new first baseman, right fielder. Left fielder, shortstop, third baseman and a whole new bullpen. This season we replaced our CFer and SS. Everything else is the same as 2012.
The difference is a fall off in performance. Last season, Buch burst out of the gate with 11 strait wins and a minuscule ERA. His drop off has been huge and probably the major contribution to our slow start. Pedroia has been a shadow of himself. He is the offensive key. When he gets hot, Ortiz will see more pitches to hit. Victorino has only played a handful of games. Uehara has been money, but he has shown signs of being human unlike last year. We can't expect him to replace last year's performance. The reason for the spotty below .500 start is not a changing core. That happened last year. The reason is a drop off in performance.