Tarnasky has good size and strength and a high fitness level. His skating is somewhat average but he compensates with hustle. Tarnasky loves to hit and work along the wall and do many of the dirty jobs that are necessary on a successful hockey club. His work ethic may be the strongest of any prospect in the Lightning organization and he is an emerging leader amongst the team's youth. He has no problem dropping the gloves to defend his teammates.
His understanding of both the offensive and defensive side of the game are still rudimentary. He doesn't have terrible hands as evidenced by his last season of junior, but he hasn't been much of an offensive threat as a pro and likely never will be. His skating still needs some work, particularly his initial burst, if he's going to compete at the NHL level.
The Lightning organization loves Tarnasky and sees him as a regular on their checking lines in the future. His offensive upside is probably very limited, but he could have a long career as a physical energy type player who plays responsible defense and can be used regularly on the penalty kill.