A ratings battle with crosstown rival WBZ-FM (98.5) "The Sports Hub" may have been the determining factor in changes being made by Boston's WEEI-AM (850). The Boston Herald reports tthat midday "Dale & Holley Show" hosts Dale Arnold and Michael Holley will be split up, with Holley joining the afternoon drive "Big Show," hosted by Glenn Ordway. Arnold will be dropped to a fill-in role on the Entercom-owned sports/talk station. The new midday show will be hosted by former Boston Red Sox infielder Lou Merloni teaming with WEEI weekend host Mike Mutnansky.