PHOENIX -- Cory Hart is the X-factor in the Milwaukee Brewers' search for a way to fill their unexpected void at first base.
Since Mat Gamel's season-ending knee injury in the first official workout of the spring, the company line has been that the in-house candidates to step in includes Alex Gonzalez, Bobby Crosby, Taylor Green and Hunter Morris.
And then there is Hart, even though he will also open the season on the disabled list. He is recovering from a Jan. 25 operation to remove debris from his right knee cap and repair a small tear to the meniscus. Doctors say Hart will be out until late May.
Hart, however, begs to differ. He expects to cut short his rehab by a month. History is on his side.
Two years ago, he suffered a strained left oblique during Spring Training, and he was in the starting lineup, playing right field, 24 games into the season. A year ago, he underwent surgery for a torn meniscus in his right knee on March 6, but was in the Opening Day lineup in right field.
"They say I'm a pretty good baseball player, but a really good rehabber," said Hart.
So when Hart says he'll be ready by late April this time ...
"His nickname is Comeback Kid," general manager Doug Melvin said. "We know not to doubt him, but this is a bit more serious than last year's surgery. We'll see."
The big day for Hart is March 8. He is scheduled to undergo an MRI exam on the knee. If everything is good, he will get the go-ahead to start working out. When it comes to working out, he doesn't hesitate, which is why Hart has beaten the expected return dates in the past.
"Once I get a green light and they say I can't hurt anything, I am ready to go at it," said Hart. "If there's pain, that won't slow me down. That's part of the rehab process. I'm not worried about that."
Hart and the rest of the Brewers do have concerns for Gamel. He was installed as the first baseman last spring, and suffered the torn ACL in his right knee on May 1 chasing a foul ball in San Diego. Hart, who had only played one game previously at first base, took over at first, and Norichika Aoki moved into right field.
Everything went well in Gamel's recovery until the first full workout this spring, when he tore the ACL in his right knee again. Now he's on another yearlong rehab. The spring started with Hart, who still has a brace on his right knee and uses a crutch, being driven to camp each day by Gamel. Now it's Hart's wife who is the chauffeur for her husband and Gamel, who was invited to live in the Harts' guest house.
"I'm more frustrated for Mat," said Hart. "I've dealt with this stuff before. Mat had his first opportunity last year cut short and now this. I'm trying to have the positive vibes rub off on him."
Meanwhile Melvin and Ron Roenicke are sorting through the first-base options.
"The fortunate thing for us is we are set at the seven other everyday position," said Melvin. "First base is the one position where we have a decision to make."
Gonzalez, the starting shortstop until he blew out his right knee in the 24th game last season, returned to the Brewers this year with the idea he would be a utility infielder. All 1,536 games he has played in the field in the big leagues have been at shortstop, but Melvin has reasons to feel good about Gonzalez's ability to step in at first.
"It is similar to what Michael Young did with the Rangers," said Melvin, who previously was general manager in Texas. "He's an outstanding middle infielder with good instincts."
Gonzalez reinforced Melvin's confidence when he made his first-base debut in an exhibition game against Cleveland on Sunday. Gonzalez made a quick spin and throw to second after fielding a ground ball, and he later picked a ball in the dirt.
Among the players the Brewers will keep an eye on this spring is Lyle Overbay, who opted last month to sign a Minor League contract with Boston instead of Milwaukee. The Red Sox's acquisition of Mike Carp from Seattle last week cut into the chances Boston will have room for Overbay. The Brewers also offered Juan Rivera a Minor League invite before he signed with the Yankees, but he is a right-handed hitter.
"Ten or 12 games into Spring Training, we will reevaluate the situation, decide if we can [fill the position] internally," said Melvin. "If do anything outside, it would be for a left-handed bat, probably."
The only left-handed in-house candidates are Taylor Green, who hit .184 in 58 games in a backup role with the Brewers last year, and prime prospect Hunter Morris, a Spring Training invitee who is coming off a big season at Double-A . Unless he has a breakout spring, however, Morris most likely will head to Triple-A.
No sense disrupting his developmental plan, particularly with Hart lingering in the background, ready for a rapid rehab, and with a track record that gives the Brewers reason to believe he will be back sooner than expected.
Tracy Ringolsby is a columnist for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.