The last road trip of the year gets kicked off with Martin Perez’s surgically-repaired arm.

Thirteen games left. Every one of them will be huge. Fortunately, the Rangers have experienced this scenario before.

The last time the Rangers had to face a critical thirteen-game stretch was the start of the Great Turnaround of 2015, back on July 22, when the Rangers had been falling like a rock.

They were nine games out of first, just two games from last, with the fifth-worst record in the American League.

They had a huge boulder to push. And a steep hill to push it up.

They were staring into the sun at three against the Anaheims, who were in first place in the West, four against the Yankees, who were in first place in the East, three against the Giants, who were knocking on first place’s door, and three against the Astros, who were inches from first.

Six games into that stretch, the Rangers were 3-3 and licking their wounds after an embarrassing 21-5 loss to the Yankees.

The grave was dug, the casket was lined up, the bulldozer was ready to fill in the hole.

But instead of ending up six-feet under, the Rangers ended up winning seven of those next eight to go nine and thirteen overall.

And thirty-five of their next fifty-five.

How did that  happen?

It’s an inexact science, the kind of debate that keeps bars stools filled and sports talk radio humming. But what is not disputable is the fact that Jon Daniels made some brilliant moves that transformed his rotation, his bullpen, his lineup, his team, his season. And, perhaps most critical of all, his career.

Very few trade deadline moves have had the impact of the series of roster rebuilds that Daniels made at the deadline, and shortly after, both in what he added and what he subtracted.

It was like building an airplane while it’s flying.

Adding Cole Hamels rebuilt the rotation. Adding Sam Dyson and “Hamels trade throw-in” Jake Diekman rebuilt the bullpen. Adding Chris Gimenez and Bobby Wilson rebuilt the spine. Adding Mike Napoli rebuilt the memory of 2011, as well as filled the gaping offensive void that had been leftfield. Adding Will Venable and Drew Stubbs rebuilt the bench with versatility, speed, and just enough offense. Subtracting Tanner Scheppers and Leonys Martin put the psyche of this team in remission.

Piece by piece, the Rangers were reconstructed, revitalized.

Now they head to Oakland for the start of the final thirteen games. Instead of being nine games out at the beginning of this thirteen-game stretch, they are one game up.

It’s turned out to be a very good season, because Jon Daniels had a very good year.

G.M.s, like players, can have bad years. Fortunately, they can have bounce-back years as well.