This is a good "problem" to have. Yeldon is solid, and looked really good yesterday. Personally, I still like Ivory better. Using him on screens this year when he has spelled LF have been very effective for the most part IMO. 

Last season, I could see a big difference running styles between Ivory and Yeldon. Ivory looked much better (aggressive and strong style) than Yeldon. It was easy to see, just to my own eyes. 
Ivory did have fumble issues, and he did it again yesterday.

I like Ivory as the #2 for this year. Next year will be a different story. Ivory will be another season older, and his price tag will probably mean that they'll move on from him anyway. 

Yeldon will be #2 next year for sure, and that's still a terrific option.

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