In 1994 the Rangers signed Will Clark, making him teammates with Jose Canseco. Thus, the biggest star on each team of the 1989 World Series were now teammates. That meant that, come spring training, fans would bring cards of both of them to sign. Here's Will Clark in spring training on his 1995 Pinnacle, about to sign a card from a pile held by a fan.
At the bottom of the pile is clearly a 1991 Fleer card. It's a bit hard to tell in this picture, but the number is pretty clearly one digit. That means it is very likely Jose Canseco. As you can see, the back of the card looks like the one being held in the picture.
I wonder if, the same day Pinnacle snapped the picture of Clark, the fan also got Canseco to sign this yellow-bordered beauty.