He left GU as a first-round pick. Four years later he's pitching for the Mariners, Sports
MLB Winter Meetings: 10 trade candidates to watch
The Trade That Saved the Seattle Mariners - The Ringer
Cardinals 2020 breakout candidate: Tyler O'Neill - The Athletic
Mariners Flip Tyler O'Neil for Marco Gonzales: Yawn or Yay?
3 trade fits for Cardinals' Tyler O' Neill
Where Seattle Mariners could look if they decide to trade for a bat - Seattle Sports
Cardinals To Promote Tyler O'Neill - MLB Trade Rumors
Get to know Marco Gonzales, the Mariners' newest pitcher - Lookout Landing