I voted for Frank, but like I said, it's very hard to evaluate offence vs. defence.  FWIW, Baseball Prospectus' WARP3 has Jackie as a significantly better player from age 28 (when he broke the colour barrier) to the end of career.  There is really little doubt that he was a better player at his peak.

National League Rookie of the Year.  National League MVP.  American League MVP.  Major League Player of the Year.  American League Triple Crown winner.  World Series MVP.  All-Star MVP.  National League Gold Glove.  Two-time league leader in OBP.  (Sixteen times in the top ten.)  Four-time league leader in slugging percentage.  (Seventeen times in the top ten.)  Three times league leader in runs scored.  (Thirteen times in the top ten.)  Fifteen times in the top ten in home runs; currently sixth all-time.  Thirteen times in the top ten in RBI; currently seventeenth all-time.  Twelve times in the top ten in walks, five times in stolen bases.  Twelve-time All-Star.

And, if you're enamoured of players shattering the colour barrier, first black manager.

Props to Jackie, salute to Brooks, tip-o'-the-hat to all other Robinsons, but there can be only one greatest, and that's Frank.

Hands down.  No contest.  Game over.

I voted Jackie.  Not because of numbers or stats.  Breaking the colour bar was huge. Changed baseball forever.Think of how different baseball would be were it not for all the black, Latino or Asian players that have come since.

 

I agree about Frank, but understand the votes for Jackie, even Brooks and Wilbert. But three people voted for Aaron Robinson? Nice player, but can someone explain? Were you thinking Hank or something?

There is really little doubt that he was a better player at his peak.

I think it's very, very close.  The war, the color line, a late start in baseball and a "wasted" year in Montreal made Jackie's prime take an odd shape, his ages 30-34 seasons.  Robinson's peak was more normal (23-31).

If I needed one player for one game and could pick the best day of his life, I'd take Frank.  If I needed one player for one season and could pick his best season, I'd take Frank ('62 or '66, can't decide which; probably 1966, since I would be willing to bet you a lot of money that no one else will win a Triple Crown in a pitcher's park in our lifetimes).

If I needed one player for one season and had to pick a composite of his five best seasons, sure I might take Jackie.  Some teams could use Frank more, some could use Jackie more. 

Here's the way I see it.  Jackie's peak is 1949 and 1951.  F. Robby's peak is harder to figure.  He's at his best offensively in 1966 and 1967, but by that point, he's an average or below average defensive rightfielder. You could probably use their age 30-32 years safely and get a fair comparison. 

At his peak, Jackie got on base as much as F. Robby relative to league standards, was absolutely devastating when on base, and played a key defensive position as well as anybody.  He had less power than F. Robby, of course, but there is no way that the power difference equalled the defensive and speed difference.  Jackie played second base as well as O-Dog at his best, and his offensive peak would fit in during Morgan's 1972-76 run.