Serve Bot Slugfest: Opelka inches past Isner in longest ATP Tour era set tiebreak 

At the Dallas Open on Saturday, a large tall glass of Serve Bot tennis was on tap. Americans Reilly Opelka and John Isner kicked off the semifinals day in Texas, and now Marcos Giron and Jenson Brooksby have a lot to live up to following their historic bout. It was a fight until "game, set, match" was called by the chair umpire—with Opelka mercifully posting a 7-6 (7), 7-6 (22) scoreline to slide into the final.

As to be expected, there wasn't a lot of long points in this match, since both are known to dictate points from the jump using the serve. The two competitors have now played 12 consecutive tiebreak sets not just because of their top-notch serving, but their ability to stay calm and collected during pressure points. It was more of the same on Saturday, but the second set officially takes the cake over all previous battles from years past.

Heading into yet another tiebreaker, no one could have imagined just how far things would go this time around. A handful of match points for Opelka erased in style by Isner, especially on Opelka's second match point in which Isner cracked his second serve down-the-tee for an ace, but Isner also saw 10 set points come and go. Neither flinched under pressure and even Tennis Channel commentator, Pam Shriver was left in disbelief.

"They got to lose a service point eventually, or else they'll never let us out of this booth," she said laughingly.

In the end, Opelka found a way to win what is now the longest tiebreak played in the ATP Tour era (since 1990). Opelka struck 39 aces with Isner serving up 21 and Opelka has now claimed nine of the last 12 tiebreaks against his countryman. It was certainly a match for the history books and the crowd ate up every second of it.

Whoever meets Opelka in Sunday's final must come prepared with the utmost focus and determination if they want a chance at the ATP 250 title.