SURPRISE, Ariz. - The Rangers have flirted with the idea of a six-man rotation before. This spring is no longer about coy flirtation, but rather hot pursuit.

As 37 pitchers took the field for the first time Thursday, general manager Jon Daniels left no doubts about the club's intent this season: They will aim to expand the starting rotation.

"We are leaning towards some variation of a six-man rotation," Daniels said in the plainest acknowledgment of the club's plans to date. "We are going to look to give guys additions rest. We see benefits to that. We think it will benefit everybody."

The variation the Rangers will try to pursue: Giving five days of rest, instead of the traditional four, to every pitcher. With additional scheduled off days this year, it means the sixth starter will occasionally be skipped. Over the first 42 games, roughly a quarter of the season, the sixth starter would likely end up with three or four fewer starts than the No. 1 starter. The Rangers, however, open the season with 14 consecutive games before an off day, meaning the No. 6 starter would get at least two turns before being skipped.

Manager Jeff Banister said he's mapped out variations that would have the No. 6 starter getting 14-16 starts if the Rangers adhered to the plan all the way through the season.

The Rangers will also aim to go with seven relievers, meaning they will likely carry more pitchers (13) than position players (12). Daniels said the Rangers reviewed their roster from 2017 and they had 13 pitchers for about two-thirds of the games before rosters were expanded in September.

"There are challenges with it," Daniels said, "but it wouldn't be all that different from what we've worked with."

The biggest criticism of a six-man rotation would be potentially limiting the top starters to a couple of fewer starts per season, maybe 29 or 30 vs. 32 or 33. The upside, the Rangers believe, is that it would significantly increase the starter's effectiveness over those starts, perhaps also allowing him to work deeper into games.

Case in point: Cole Hamels, the Rangers top pitcher. The Rangers see it as not necessarily limiting Hamels, but helping to make him significantly more effective when he starts. Over the last three seasons, Hamels averages 6 2/3 innings and has a 2.67 ERA when he starts five days after his previous start compared to 6 1/3 innings and a 3.96 ERA on four days of rest. He also allows a .615 OPS on five days vs. .708 on four.

"We definitely want to explore that avenue," Banister said. "We've looked at the numbers and how they've played out. Some of the numbers play out well. And you look at the volume of guys who go 200 innings now and it continues to shrink. We think we have an opportunity to keep them fresher. You would think, in theory, it might also allow them to go deeper."

Theory, however, is a key word. Looking at the individual starters in the Rangers' camp, there is no definitive trend to their performance on four days vs. five. Some show a significant uptick. Some have performed better on four days. But there is a variable there, too. Four days has been the norm and five typically the aberration; if five days becomes the more normal routine, pitchers might get more comfortable with the schedule and truly see benefits from extra rest.

In the meantime, though, the Rangers will prepare Hamels, Doug Fister, Matt Moore and Martin Perez, once he's cleared to resume full activities, to pitch on four days of rest. They are pursuing the six-man rotation, but haven't yet committed to it. It's easier to prepare pitchers one way and then give them extra rest once the season starts than to prepare them for extra rest, then have to use them more frequently.