The £5million club record signing was met by some familiar old faces as he posed in his new Hammers shirt for the gathered press - just hours after stepping off a plane following Scotland's disappointing defeat in Belgium on Wednesday night.
Despite completing his transfer from Sunderland early last week, the 30-year-old had been on international duty with Craig Brown's men as their World Cup dream disappeared thanks to a goalless draw at home to Croatia and a 2-0 loss against last year's Euro 2000 co-hosts.
However, a smile returned to his face as he finally began his Upton Park career and looked forward to making his second debut against Derby County on Saturday.
"It's great to be back here," he enthused, "and I'm really looking forward to the challenge ahead.
"I can't wait to play against Derby on Saturday, but I'm looking forward even more to playing at Upton Park again.
"The fans here were always great to me and it will be fantastic to play in front of them again."
Don also brushed off the view from many media 'experts' that his move back to London was a backward step, insisting: "There's no way I would have left Sunderland to join a club who I didn't think had the potential to be better.
"There are some wonderful players here and I'm quite happy that so many people are tipping West Ham to struggle. That takes any pressure off us, and I thrive on proving people wrong anyway.
"I'm sure that we can enjoy some success here. My last spell at the club didn't go as well as I would have liked it to, so I've got plenty to make up for and I just can't wait to get going now."