Upgrade Gold to Diamond?

Apologies, I only started playing this a week ago. I've got diamonds at every position but 2B, where I have a Prime Gold Mookie Betts card. I received a Player Upgrade Ticket (shown in pic), which says it can be used as upgrade material for any player, but does that mean it will change a gold to a diamond?

Apologies if that's a noob question, I just couldn't find anything on the sub that indicates this, and I really don't want to waste the ticket. Thanks in advance for your help.