Cardinals fans have another obvious reason to be upset with John Mozeliak

St. Louis Cardinals president of baseball operations John Mozeliak was booed at the team's opening day. It was obvious how the fans felt about his roster building.

Mozeliak promised several frontline starting pitchers, and instead settled on Sonny Gray and...Kyle Gibson/Lance Lynn. Gray is capable, don't get me wrong, but the rest of the Cardinals rotation leaves a lot to be desired.

Unfortunately for Cardinals fans, Mozeliak's mistakes don't end with the starting rotation, or prematurely extending manager Oli Marmol just to avoid controversy. Trading Tyler O'Neill could come back to haunt St. Louis.

The Cardinals outfield has been crowded for over a season. O'Neill was the odd man out this winter, as he was traded to the Boston Red Sox. Dylan Carlson remains and could serve as trade bait come the deadline if St. Louis is out of contention. However, there's a chance Mozeliak dealt the wrong outfielder, as O'Neill is playing very well so far this season.

Will the St. Louis Cardinals regret trading Tyler O'Neill?

In just nine games, O'Neill is slashing .357/.514/.893 with an OPS of 1.406. It's way too early to make a harsh judgement on O'Neill this season, but St. Louis didn't receive much in return for his services. If he continues to put up decent numbers as a mainstay in the Boston outfield, St. Louis fans will be wondering what if about another outfielder they let get away. Look no further than Adolis Garcia and Randy Arozarena for evidence.

As Andrew Wang of Redbird Rants suggested, trading O'Neill could be a move Mozeliak regrets by midseason:

"With Nootbaar and Edman on the IL to start the season, O'Neill sure would have come in handy as another outfield option. Now that it looks like he's finally healthy, he's showing shades of 2021 in Boston. He homered for a record 5th consecutive Opening Day, and he hasn't slowed down," Wang wrote.

O'Neill got on Oli Marmol's bad side early last season when the manager called out his outfielder to the media for not hustling. O'Neill responded by saying he didn't want to aggravate a past leg injury, which makes sense given his extensive history on the IL.

A change of scenery has benefitted O'Neill so far in 2024.