ARLINGTON -- The American League West champion Rangers are expected to go with Cole Hamels and Yu Darvish as their top two starters in the postseason.
Hamels has a long track record of playoff success, going 7-5 with a 3.03 ERA in 15 starts. Darvish has made just one start in the postseason -- a loss against the Orioles in 2012.
Hamels has been healthy for the past two seasons and made 32 starts each year. Darvish has made 17 starts this season after missing all of last year while recovering from Tommy John elbow reconstruction surgery.
When it comes to the postseason and Texas' top two starters, Hamels is the known quantity. Darvish is the X-factor.
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"I think there is an unknown until a guy goes through it," Rangers manager Jeff Banister said. "There is a lot of unknown until you put skins on the wall. However, these are our two main guys. I don't think I'm going to turn off the hot water just yet. It's not like we are going to change."
The X-factor is a guy who could make or break a team during a postseason series. Darvish could be that for Texas, even though he would likely start just once in the AL Division Series and twice in both the AL Championship Series and the World Series.
Darvish has the ability to dominate a game, especially under the glare of the big stage. But he is inexperienced in postseason play, and he has still been putting the finishing touches on his recovery from Tommy John surgery.
"I'm very much looking forward to it," Darvish said. "I pitched in one postseason game and that was it. It's going to be on the bigger stage, and I'm looking forward to pitching in it."
Darvish's only postseason start came in the 2012 AL Wild Card Game against the Orioles, and he did not pitch poorly. The right-hander went 6 2/3 innings and allowed three runs (two earned) on seven hits and no walks while striking out seven. But O's starter Joe Saunders was better, and the Rangers were eliminated in a 5-1 loss at Globe Life Park.

"I feel like I'm a better pitcher now, mentally and mechanically," Darvish said. "I have been trying a lot of stuff, and my last outing gave me more confidence. I'm happy where I am at."
Darvish's last outing came against the A's last Saturday, when he threw seven scoreless innings in a 5-0 victory. He allowed two hits, walked a batter and struck out nine. Darvish enters his last start of the regular season on Friday against the Rays with a record of 6-5, a 3.53 ERA, a 1.14 WHIP and 11.45 strikeouts per nine innings.
Darvish has made significant progress since Tommy John surgery, and in many ways, he is as good or better than before.
"I think he has overcome the tough process that the arm is OK," Banister said. "That is significant to every Tommy John patient; they have to have confidence to let it go on every pitch and know this is the new normal for them.
"The command can be an issue, especially the secondary stuff. The feel and command is the last to come. We've seen in his last few starts that part has ramped up."
There is also stamina and endurance. Texas has been cautious with Darvish's pitch counts during the season, and the club has maneuvered its rotation on several occasions to give him extra rest. Those are no longer priorities. Restraints are removed in the postseason, when it becomes solely about winning each game.
"I think we've gotten to that point in the last couple of outings," Banister said.
Now, the Rangers are headed to postseason. The big test for the team's X-factor is still to come.