Stubbornness and confidence are characteristic of most professional athletes. Despite the connections they've made and the checks they've cashed, they always want more.
But the following players would only be hurting themselves by continuing their careers beyond the 2013 season.
Giambi used to be an on-base machine.
After the 2012 season, Jason Giambi was ready for the next chapter of his baseball career.
He interviewed for the vacant manager's job on the Colorado Rockies. The club took him seriously as a candidate but ultimately selected Walt Weiss. Even then, Giambi considered coaching hitters (via Troy E. Renck, The Denver Post).
The former AL MVP is a decade removed from his prime. Hefty and greying at 42 years old, he's a defensive liability that National League teams can't use.
Fortunately, the Cleveland Indians gave the injury-prone designated hitter an opportunity this spring. His 2013 debut could come as early as April 9, the first day he'll be eligible for activation after suffering a back strain.
Giambi batted .225/.372/.303 for the Rockies last summer, and that was augmented by the high altitude of Coors Field. Though a positive clubhouse presence, he simply doesn't have enough ability to hog a spot on the 25-man roster.
Oswalt dominated in his rookie season and never looked back.
Roy Oswalt waited until late May to join the 2012 Texas Rangers.
Both sides regret that experiment. The right-hander pitched significantly below replacement level for a seven-figure salary. Because of that, his outlook seems bleak, even at the reasonable age of 35.
Toward the end of spring training, MLB Trade Rumors reported that Oswalt is working out near his Mississippi home and hoping to latch on with a contender. Despite plenty of individual excellence over the past dozen years, he still yearns for a championship.
The two-time 20-game winner is gradually losing velocity, according to FanGraphs. But he has too much pride to accept the role of a back-end starter or middle reliever, and no teams want to put up with his whining (via The Dallas Morning News).
Oswalt ought to be content with his career earnings (nearly $100 million).
Carpenter, a three-time All-Star, won the 2005 NL Cy Young Award.
Don't expect Chris Carpenter to officially retire. Ever.
"I'll never say that word," he insisted during a February press conference (h/t Jordan Palmer of kdsk.com).
If this workhorse were healthy next offseason, his agent would receive calls from all 30 MLB general managers. He's a fierce and talented competitor with invaluable advice for developing players.
In reality, the New Hampshire native might never fully overcome chronic numbness and sensitivity in his shoulder, neck and hands. Even radical surgery for thoracic outlet syndrome only provided temporary relief.
Unlike Roy Oswalt, Carp already has two championships. He played an integral role on both the 2006 and 2011 St. Louis Cardinals and doesn't have anything left to prove.
Of all the veterans on this list, Manny Ramirez is the only one with statistics so far in the 2013 regular season.
This two-run bomb from Wednesday night highlighted a three-hit performance that upped his batting average in the Chinese Professional Baseball League to .318. He is leading the EDA Rhinos—a team with just one playoff appearance since 2007—back to relevance.
Ramirez's notorious personality and lousy work ethic for non-hitting tasks made him unpopular in the majors. Coupled with his use of banned substances, it's no wonder he didn't receive any domestic offers.
The successful slugger hopes gaudy production in a dysfunctional foreign circuit (via The New York Times) will convince MLB executives to overlook his past indiscretions.
He should call it quits rather than hang onto that pipe dream.
Vlad's power and contact ability make him a future Hall of Famer.
Ken Rosenthal of Fox Sports broke the news of Vladimir Guerrero's comeback attempt.
The Long Island Ducks compete in the Atlantic League of Professional Baseball, which is an independent league.
"My ultimate goal is to make it back to the major leagues and attempt to reach 500 home runs as soon as possible," Guerrero admitted in a statement (via Jerry Crasnick, ESPN.com). He believes staying in the U.S. makes him more visible to MLB teams, which explains why he declined contracts to go to Taiwan and Quebec.
But Vladdy's reputation is not tarnished by performance-enhancing drugs, and injuries have seldom kept him off the field. The former five-tool talent is bound for Cooperstown, regardless of how much he pads his career totals.
Why can't he be content with a .318/.379/.553 batting line and only 449 home runs?
Players have such a strange fascination with round numbers.