Wales centre Hadleigh Parkes dedicated their Grand Slam to the victims of the attacks on two mosques in New Zealand that left 50 dead and dozens wounded.
The 31-year-old, who was born in New Zealand, scored Wales' try in the Grand Slam-clinching 25-7 win over Ireland.
"It's terrible. You kind of think New Zealand is like a safe haven," he said.
"For the people of Christchurch, for the Muslim community, it's shocking. It is heartbreaking to hear about that kind of thing."
A minute's silence was held before the match, during which New Zealand born fly-half Gareth Anscombe kicked 20 points for Wales.
"I am really thankful for the minute's silence," added Scarlets centre Parkes, who has won 14 caps since qualifying for Wales in 2017.
'Expectation is nice'
Wales' win sent them to second in World Rugby's rankings, one place behind New Zealand.
Parkes accepts Wales' success under Warren Gatland means he and his team-mates must accept they are among the favourites to win the 2019 World Cup in Japan, which takes place between 20 September and 2 November.
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"It's nice to have a bit of expectation on you," said Parkes.
"There is a lot of rugby still to be played - hopefully it will be a good year for the Welsh people."
Parkes also added his voice to those praising Wales captain and lock Alun Wyn Jones for his leadership and performances during the campaign.
"He has to be one of the greats. That's pretty simple," said Parkes.
"What he does for the Ospreys, what he has done for Wales for a number of years, he has to go down as one of the greats.
"He is the leader, he is the one you look to, he's the one who steps up week in, week out. Every game he puts in a performance.
"He is a very nice man as well, that must be said, a very humble man. But what a leader, what a captain, what a bloke."
Having played for Super Rugby sides Blues and Hurricanes as well as Auckland and Waikato in New Zealand, Parkes also had a stint with Southern Kings in South Africa before joining Scarlets from Auckland in December 2014.
He said: "I am very grateful and humbled by the opportunity that I've been given by the managing team here, and also the people in west Wales at the Scarlets.
"It's been an amazing four-and-a-half years so far. I have to pinch myself.
"You dream about these moments. The England Test was amazing, but this was just another step up again."