Tina Joseph of B2T Training illustrates that, while the Project Manager and Business Analyst roles overlap, they have very distinctly different objectives and focus... requiring different skills and training:

The PM delivers a project charter which defines the project, the objectives, and a list of project participants including resources. The BA delivers a project scope which defines the boundaries of what is going to be analyzed as part of the project including high-level processes and a more detailed analysis of the root cause of the problem being addressed.  Overall, the roles have a different function. The PM is ultimately responsible for the project completion, its budget, resources, and a timely completion. The BA is responsible for fully understanding the business problem and providing complete analysis to ensure that the solution best meets the needs of the business. These roles have completely different focuses requiring unique training for each role.

Have you ever driven a nail with a crescent wrench? I have. What a noisy mess that is! Use the correct resource for the business analysis job... read Tina's full post here.