Opening acts: Tyler O'Neill's bind, Jordan Walker's debut, and pitching glitches

The season-opening home stand ended with sweep by Atlanta and the first true stress tests of the Cardinals -- one long predicted and the other completely unexpected. Once the cars had been returned to their sales lots and the Clydesdales to their stable, the Cardinals flashed a deep, persistent offense, as advertised. Jordan Walker, the 20-year-old rookie, punctuated his strong debut with his first career MLB homer. The Cardinals also had abbreviated, choppy, and messy starts from the rotation. The Cardinals leave for their first road trip of the season with rotation ERA higher than 7.00. They allowed 42 hits, and that includes five no-hit innings from Jack Flaherty. And that's not the only question lurking. Manager Oliver Marmol questioned Tyler O'Neill's effort on a pivotal play that yielded an out at the plate, and O'Neill was not in the lineup for the series finale vs. Atlanta. O'Neill defended himself, insisting it was not a lack of hustle, and he's eager to prove differently. It's not the first time Marmol has questioned a player's effort publicly, but it is the first time this season and it's earlier than ever, leading to a two-pronged test of the Cardinals: Who will lead the rotation through turbulence, and how will the clubhouse react to the O'Neill decision? St. Louis Post-Dispatch sports columnist Ben Frederickson joins baseball writer Derrick Goold at Busch Stadium to discuss. The Best Podcast in Baseball, sponsored by Closets by Design of St. Louis, is a production of the St. Louis Post-Dispatch, StlToday.com, and Derrick Goold. See omnystudio.com/listener for privacy information.