Mozeliak told the St. Louis Post-Dispatch that the Cardinals' circumstances this past offseason, specifically the death of 22-year-old right fielder Oscar Taveras, factored into the four-player trade with the Atlanta Braves that sent Heyward to St. Louis.
"I think whenever you make those kind of deals, there are reasons behind it," Mozeliak told the Post-Dispatch. "And at the time, we felt that we had to do something. Not only looking at how we want this club to be put together, but we did not feel like there might be any other opportunities that would meet the type of criteria we're looking for."
Heyward, an All-Star and two-time Gold Glove winner during his five-year stint with Atlanta, entered play Saturday with a .241 batting average, five home runs and just 14 RBIs in 45 games with St. Louis.
Meanwhile, Miller has thrived with the Braves, going 5-2 with a 1.48 ERA -- the best in the majors -- over his first 10 starts. The 22-year-old Jenkins also gotten off to a promising start at Double-A Mississippi, posting a 3.00 ERA in 10 outings.
But Mozeliak believes that the 25-year-old Heyward, who is playing in the final year of his contract, has more than enough talent to justify parting with Miller and Jenkins.
"I still think there's more in the tank for [Heyward]," Mozeliak said. "He's a capable offensive player. I do think he's going to have to make some adjustments. When you look at the type of talent he is, and the type of athlete he is, expectations are high. Our game is pretty simple: you do or you don't. I do think he's the type of athlete that can do that. Historically he has."