Complex sentence: Swanson attended Vanderbilt University and played college baseball for the Vanderbilt Commodores, before the Arizona Diamondbacks selected him first overall the 2015 Major League Baseball Draft.
Split into simpler sentences: Swanson attended Vanderbilt University and played college baseball for the Vanderbilt Commodores. The Arizona Diamondbacks selected him first overall in the 2015 Major League Baseball Draft.