In any playoff series, winning the first game is obviously important. More so for the Texas Rangers.
Whether the current players know it or not, they have the collective history of the franchise weighing them down. Nearly 40 years in Texas, and one playoff win. It's not impossible to overcome, as the Red Sox did in 2004 and the White Sox did in 2005 (winning a World Series after nearly 80 years without), but it's not easy.
And that's why getting off to a 1-0 series lead is almost critical. A 1-0 lead means that this team is already as successful as any team in franchise history (the 1996 team won Game 1 in New York). A 1-0 lead is proof, immediate proof, that this team can win in the playoffs. A 1-0 lead means the Rangers are playing with house money.
On the other hand, a 0-1 deficit would be scary. It would be the 10th consecutive playoff loss for the team (although the 9th came more than a decade ago). Questions in the clubhouse following the game will eventually lead here. The players know -- they're aware of the franchise's playoff futility even though none of them were a part of it. But that seed of doubt will get planted, and while it's not impossible to overcome, it certainly would not be helpful.