The Welsh will have to beat defending champion Ireland — a team Gatland coach from 1998-2001 — in Cardiff next Saturday for the sweep. Gatland, coach of Wales for more than 11 years, is stepping down after the Rugby World Cup this year.
"There's no doubt it'll be emotional," Gatland said. "It's St. Patrick's Day next week so the Irish will be chomping at the bit. It'll be a great occasion and you won't be able to get a ticket anywhere.
"The competition is still open. England will think if we get knocked over, they'll have a chance to win. So will Ireland. "We want to win this championship and the only way we can is by getting the Grand Slam. If we do that, I can promise you there will be some pretty huge celebrations afterwards.
"We've got to regroup, get home tomorrow, look at the banged up bodies and plan as well as we can for this week. The beauty about that is we get another day over Ireland because they play tomorrow (against France) so it'll be a challenge for them."
Gatland eased fears about their only apparent injury worry after beating Scotland. Star fullback Liam Williams left the field early in the second half cradling his right arm after tackling Allan Dell. He took a stinger and should be OK, Gatland said.
He could become the first coach to win three Grand Slams. His previous slams were in 2008 and 2012. "I'm excited about it," he said. "It's a dream and we could do something special as a group of players. We're 13 in a row now (a national record) and we could make it 14 next week.
"I'm a great believer in being the eternal optimist. You break a record and no one can take it away from you. "When you get those opportunities, you have to grasp them with both hands. You have to go out and not have any regrets, and I have no doubt this group will have no regrets.
"If that Welsh crowd turn up and do what they did against England, then there's no doubt that the atmosphere and the passion and the drive will have a significant impact."
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