SCOTTSDALE, Ariz. -- D-backs prospect Tyler Mark walked off under his own power after being struck in the head by a line drive off the bat of Vladimir Guerrero Jr. in the third inning of an Arizona Fall League game on Wednesday night at Salt River Fields. On Thursday, Mark tweeted that "all is well" and thanked his fans for the texts, tweets and prayers.
Mark, an MLB Urban Youth Academy/Boys and Girls Clubs of Venice RBI alumnus who was selected in the sixth round of the 2015 Draft, delivered an 80-mph slider that Guerrero lined back up the middle with an exit velocity of 103.24 mph, per Statcast™.
The ball ricocheted off Mark into the third-base dugout for a ground-rule double.

Mark was down on the ground for a few moments, but he eventually stood up and walked into the Salt River Rafters' dugout.
Mark, 23, reached Double-A this season and went 2-2 with a 5.40 ERA over 10 appearances for Jackson after being promoted from Class A Advanced Visalia. The right-hander went 3-4 with a 2.29 ERA in 45 games between the two affiliates.