A motherboard I ordered from eBay come with a damaged trace (among other surprises).

There were several possible approaches to this. What I ended up doing was folding back the copper traces and soldering a resistor lead that I had cut to size as a brace and flow solder over the entirety to secure it in place.

I considered cutting the trace and running a thin piece of wire but I felt that if the lifted trace could be made to stay flat beneath a bit of lead then it would have a larger surface area to bond to and be stronger overall. If this didn't work then I could always cut the traces and run a wire later.

This ended up working fine and the repair is very sturdy. I did have to flatten the lead in my pliers first to keep it from rolling away.

Here is a close up before and after I applied a bit of kapton tape to add a bit of extra protection.

The finished repair zoomed out for scale.