ARLINGTON -- With Mike Napoli coming on board to play first base, Josh Hamilton and the designated hitter situation are the biggest mysteries surrounding the Rangers going into Spring Training.
Hamilton, who agreed to a Minor League contract last month after missing all of last season because of multiple left knee surgeries, was planning to try to play first base in Spring Training. That may still be the plan, but it's obvious Napoli will be the regular first baseman.
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Besides being the power bat needed for the middle of the lineup, Napoli has also developed into an accomplished defensive first baseman. That's critical given the importance manager Jeff Banister puts on defense.

Hamilton could also see time in the outfield, but his time there will be limited because of his physical issues. If Hamilton does work his way back into the lineup, it's likely that it will mainly be at DH.
It could be a crowded position, something that Banister and general manager Jon Daniels talked about at a pre-Spring Training media briefing on Wednesday.
"We have a number of guys with us we like in competition that will give [Banister] some options at DH," Daniels said. "We've talked this winter about not having a full-time 162-game DH, but having a roster that will allow Jeff to move guys through there."
The first step will be to see if Hamilton, 35, has anything left. He hasn't played since 2015, and he only appeared in 50 games that season, hitting .253 with eight home runs, 25 RBIs and a .441 slugging percentage. He was 3-for-18 in a five-game American League Division Series against the Blue Jays.
Hamilton has been cleared medically and has been working out lately in Arlington.
"I've been able to talk to Josh from time to time," Banister said. "He has been working out here and looks good. When we get him on the field and into games, we'll know better where he is at. I will say he's got great energy, he is moving around the field and his bat has been loud. We'll see how he is in camp. It comes down to communication between him and I on where he is at."
There has been some speculation that Shin-Soo Choo could get a significant number of at-bats at DH. Injuries limited Choo to 48 games last season. But right now he is viewed as the Rangers' right fielder and one of several players who will potentially revolve through the DH position.
"He is an outfielder, right fielder," Banister said. "This is an opportunity for Choo to get back on his legs and into the game. Choo is a huge part of our success. We definitely missed him every day last year. To have sustained success, we have to him on the field and healthy."
Choo said he is not ready to be a full-time DH, although he would be willing to do it one to two times a week. If he re-establishes himself in right field, then the Rangers have a set outfield with Carlos Gomez in center and Nomar Mazara in left. Napoli also gives the Rangers a set infield with third baseman Adrian Beltre, shortstop Elvis Andrus and second baseman Rougned Odor.
The Rangers have not yet officially announced Napoli's signing, and Daniels danced around the question at the media briefing.
"All winter we have been engaged at first base/DH," Daniels said. "We know Napoli. ... He's a player we have talked to."
The Rangers have plenty of depth behind their set lineup. Veteran first baseman James Loney, infielders Will Middlebrooks and Doug Bernier and outfielders Travis Snider, Cesar Puello and Jared Hoying are coming to camp on Minor League contracts.
Ryan Rua, Jurickson Profar, Hanser Alberto and Drew Robinson give Texas utility players with tremendous versatility, outfielder Delino DeShields will be trying to regain a starting role and the Rangers will take a hard look at slugging prodigies Joey Gallo and Ronald Guzman.
There is much to sort out, but Hamilton is at the top of the list.