Tristan Thompson Holding Hands with Mystery Woman After Clubbing in Greece

Tristan Thompson is having no problem finding companionship on his trip to Greece ... a getaway on the heels of news he and Khloe Kardashian are expecting a baby together via surrogate.

TT -- decked out in a floral-pattern shirt -- was spotted walking hand in hand through the streets of Mykonos with a mystery woman around 5 AM Sunday morning. Tristan had previously been partying at a club called Bonbonniere ... so it's possible he met her while out.

It's not the first time we've seen the NBA player out partying 'til the late hours of the night overseas ... he was at the same club Friday surrounded by several women and smoking hookah.

Of course, the trip to Greece comes just days after TMZ broke the story Tristan and Khloe are expecting a baby boy via surrogate.

What's not clear is when the baby was or is expected to be born. When we broke the story Wednesday, we were told the birth was imminent, and it was even possible the baby had already arrived.