This is the first staging of the World Cup since 1996 when O'Brien and Doherty were two of the three players in the Irish side that lost to Scotland 10-7 in the final.
The format now features two-man teams and Ireland must win their next match against Egypt on Wednesday.
Former World Champion Ken Doherty of Ireland sits and watches as Pakistan’s Muhammad Sajjad attempts to clear the table during their PTT-EGAT Snooker World Cup opening match in Bangkok, Monday, July 11.
"We're very disappointed to lose but it's amazing that we both made a century break each but lost the match 3-2," said Doherty.
"There will be a lot of shocks and surprises and it's very hard to get into rhythm, especially with the doubles match.
"It's a disappointing start but every frame counts so that's a good thing so if we beat Germany or Egypt 4-1 or 5-0 then we're right back in it.
"Pakistan and India always have good cueists and they have a tradition of producing good players over the years. They will be a test for any of the other teams in our group so it won't be as straight forward as it looks.
"Sindhu Pulsirivong (the head of the Billiard Sports Association of Thailand) has done a great job to bring the World Cup back. He's been the driving force in snooker in Asia, not only Thailand. Everyone is over the moon that we're back here in Thailand playing."
"To lose the first game is a disappointing start but if we had won the doubles and won 3-2 we would've been satisfied," added O'Brien.
"But the fellow (Sahid Aftab) that beat us both played really well so as the week progresses losing 3-2 might not look that bad.
"It was always going to be tough and take us four games and even if we had won 5-0 nothing would've been decided.
"It's fantastic to be back in Thailand. We never thought that it would take 15 years after 1996 for the next event. But hopefully it will be every two years from now on. The hotel is fantastic and the Thai people love their snooker and it shows how strong the game is worldwide."
The Thailand second team of Thepchaiya Un-Nooh and Passakorn Sunwannawat made a winning start as they defeated Afghanistan 3-2 with Un-Nooh beating Mohammad Saleh in the decisive singles match.
Un-Nooh also won his earlier singles encounter against Mohammad Rais, while Thailand triumphed in the doubles match.
Thepchaiya Un-Nooh said: "We've trained for this so I'm happy with the win. In the last game when we had a chance I knew we would win.
"With this way of playing you have to be really careful and every shot is important. Our next game will be Hong Kong and this is the deciding match for us as if we win we're going to have a chance of going into the next round."
Team-mate Passakorn Sunwannawat added: "We're not yet at our target of performance and we wanted to win 4-1. But today was really good as it's only a short game and we needed to make a good start."