As trade rumors continue to swirl, one of the offseasons biggest trade chips, Diamondbacks‘ outfielder Justin Upton, is looking less and less likely to be moved.

According to Jon Heyman of CBSSports, Diamondbacks owner Ken Kendrick said that there is a “very high likelihood” that Upton will still with the team come Opening Day. Another member of the organization said Upton has a 90 percent chance of sticking around.

This is not the first time that the Diamondbacks have listened to offers on Upton, only to then pull him off the table.  But this time around, the team should have pulled the trigger on a deal.

Taken first overall in the 2005 draft out of high school, Upton made his big league debut just two years later at the age of 19.

By 21, he was an All-Star putting together a .300 BA, 26 HR, 86 RBI, 20 SB season and looking every bit the part of a budding superstar.

After a down season in 2010, he rebounded with a .289 BA, 31 HR, 88 RBI, 21 SB season in 2011 as he helped the Diamondbacks to a surprise postseason trip. 

Upton finished fourth in MVP voting that year.

He again took a step back this past season though, hitting just .280 BA, 17 HR and 67 RBI. It was not a bad season, as he scored a career-high 107 runs and improved his walk rate from the previous season, but it is safe to say that this is not where people expected Upton to be at the age of 25.

Despite his failure to truly breakout, he remains an intriguing trade target to a number of teams for more reasons than one.

The Diamondbacks managed to lock him into a six-year, $50 million deal prior to the 2010 season and he has three years and $38.5 million remaining on that deal.

This makes him a relative bargain, given his production and upside.

And it’s that upside that keeps trade suitors coming back.  At any point, Upton could put it all together and begin a decade long streak of .300 BA, 30 HR, 100 RBI, 30 SB seasons.

It’s that upside that is the biggest reason why the Diamondbacks should have moved Upton this offseason.

Even coming off of a down season, his value may never be higher than it is right now with three years of control and plenty of time for teams to still dream of what he could become.

That’s not to say that that same upside won’t keep teams coming back to pursue him if he’s made available again. Look no further than Upton’s brother, B.J., for evidence of that.

The 28-year-old has put up an average line of .242 BA, 20 HR, 69 RBI, 38 SB the past four seasons.

Now he stands to cash in on the free agent market as much because of his power/speed combination as because of the hope that he will find the form that made him a .300 BA, 24 HR, 82 RBI, 22 SB player back in 2007 at the age of 22.

Yes, there will always be a market for Justin Upton if the Diamondbacks opt to move him down the road, and the Diamondbacks have as much of a reason to buy into the hope that he’ll break out as any team that may look to acquire him.

That said, an outfield of Gerardo Parra, Adam Eaton and Jason Kubel, with top prospect A.J. Pollock in the mix is still strong.

The young pitching staff is impressive, the bullpen is deep and the offense has plenty of other firepower in guys like Aaron Hill, Miguel Montero and Paul Goldschmidt.

The Diamondbacks are a team on the fringe of contention, and while dealing Upton may seem like a step in the wrong direction, it could just as easily be what pushes them over the top in the NL West.

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