Nationals Acquire Sean Doolittle, Ryan Madson - MLB Trade Rumors
Sean Doolittle retires after 11 MLB seasons with a 'full heart
Sean Doolittle Announces Retirement - MLB Trade Rumors
Brad Hand - Wikipedia
Sean Doolittle, Baseball's Left-Wing Lefty, Retires
A's Pitcher Sean Doolittle Turns Plan B Into Good Career Move - The New York Times
Jose Castillo on comeback trail again for Padres - The San Diego Union-Tribune
Sean Doolittle retires
Whether on the mound or for refugees in need, relief is a calling for the A's' Sean Doolittle - Los Angeles Times
The Nationals have a lefty reliever conundrum - The Washington Post