Coming into this season, I was most excited to see 2 Cubs prospects. Looks like they both get the call within a matter of days of each other. Cade Horton debuted over the weekend, Moises Ballesteros to be called up today. But, what's the corresponding roster move? No team needs 3 catchers, but the Cubs catching corps this year is unmatched. 3 things to watch: Ballesteros call-up, what's happening at third base and who exactly is Ryan Pressly? Plus, news and notes from around Major League Baseball.