Morning Mound Visit: MLB to begin foreign substance enforcement June 21

Anthony Castrovince | MLB.com: MLB issued new guidance on a foreign substance crackdown that will begin June 21. Pitchers caught with any grip enhancing substance other than the rosin provided on the mound will receive a 10-game suspension.

Adam Sanford | DRays Bay: Tyler Glasnow has a partially torn UCL and a flexor strain. The righty hopes to avoid Tommy John and will attempt to rehab the injury. Glasnow felt elbow tightness in his start against the White Sox on Monday, and he attributed his injury to a tighter grip to compensate for not using sunscreen-and-rosin.

Devan Fink | FanGraphs: Jacob deGrom is on an entirely other level right now. Hitters are so hopeless against him that they would actually fare better if they didn’t have a bat.

Quick Hits

After falling behind to a 7-0 deficit, the Giants came back with an eighth-inning grand slam off the bat of Mike Yastrzemski to secure a 9-8 win. The Diamondbacks have now lost 21 road games in a row.

Down by one in the 10th, José Altuve hit a walk-off grand slam to lift the Astros over the Rangers 6-3.

Chris Flexen struck out eight across eight shutout innings to give the Mariners a 10-0 win over the Twins.