It was a tough call between Dempster and Harrison, but I think in the end Dempster has to be the go-to guy the rest of the season. This may seem obvious because the Rangers traded for him, but it was not a slam dunk like Cliff Lee a couple years ago.
Harrison is having a fine season, but he may not be ready for the responsibility yet.
The Rangers needed a difference maker when they traded for Dempster, and he has the ability to be that. He may not have the flashy hardware that other pitchers have, but he is a seasoned veteran who still has a lot to prove down the stretch.
The Rangers have played in big series without a No. 1 guy before, and it was very difficult. They need a trendsetter; someone who can keep losing streaks to a minimum, or continue the momentum gained from winning streaks.
If Texas wants to accomplish its goals this season, Dempster has to pitch like he did with the Cubs.