Of course, there were plenty of reminders in the players' lockers.
Major League Baseball stepped up its "Going to Bat Against Breast Cancer" initiative past the traditional pink bats, wristbands and cleats. This season, the pink was woven into the uniform design as well.
The Cardinals' iconic birds on the bat logo featured a pink bat, and they wore gray caps with pink lettering.
"I've never been this excited to wear pink," said Cardinals outfielder Stephen Piscotty, who treated his mom to a four-hit day. "Obviously shows a lot of support for my mom and all that she's done for me."
Mother's Day is new for reliever Seung Hwan Oh, who celebrates Parent's Day in his native Korea. Putting on the pink was a new experience for him.
"Strange, but it's really interesting, and I appreciate it because I've only seen it on the televisions when I've been over in Korea and Japan," Oh said. "It's pretty interesting, but nice."
Matheny was reflective on his mother's influence.
"She didn't get too caught up in baseball or sports," Matheny said. "She was a stickler on grades and how I treated people and how I handled certain things. As far as baseball goes, she was one of the greatest baseball moms, because all she did was cheer, and I never had to answer why I swung at a ball in the dirt or threw a ball away. She was there and just happy to be there watching."
Authentic game-used Louisville Slugger pink bats and other gear from Mother's Day games will be auctioned exclusively at MLB.com, with proceeds benefiting the fight against breast cancer. The complete Mother's Day collection -- which includes the special caps and jerseys being worn by players on Sunday -- is available at the MLB.com Shop.
Joe Harris is a contributor to MLB.com based in St. Louis.