1961 Thomas Cup knockout stage

The knockout stage for the 1961 Thomas Cup began on 1 June 1961 with the first-round knockout and ended on 11 June with the final tie.

Qualified teams
The teams that won their zonal tie qualified for the final knockout stage.

First round
The inter-zone playoffs in Jakarta began on the first two days of June with Thailand beating Australia without the loss of a match or a game. Denmark then defeated the USA 7–2, but even in victory Danish problems with the heat and humidity were evident as players hailed by some as the best in the world often struggled against less talented opponents who, as Californians, were more accustomed to hot gymnasiums.

Denmark vs Thailand
The Danes' contest against Thailand fully demonstrated this weakness. A team entirely composed of either past, present, or future All-England champions was decisively beaten by a team composed of players who would never win that individual honor. Erland Kops and Finn Kobbero defeated the Thai number two Somsook Boonyasukhanonda comfortably, but both were beaten by young Channarong Ratanaseangsuang. Most shockingly, the famous doubles team of Kobbero and Hammergaard Hansen was beaten by both Thai pairs who swept all four doubles matches. Thus Thailand completed its run to the challenge round with an impressive 7–2 victory over Denmark.

Indonesia vs Thailand
The task of beating a strong Indonesian team in Jakarta's Senayan Stadium was possibly rendered even more difficult for Thailand when "neutral" officials and linesmen failed to arrive from Malaya. As they had done three years earlier in Singapore, the Indonesians swept all five singles matches. Ratanaseangsuang was unable to produce the consistency he had displayed against Kops and Kobbero and lost tamely to Indonesia's Tan Joe Hok and Ferry Sonneville. Boonyasukhanonda was simply not in the class of the two Indonesians, whose careers would be hallmarked by their Thomas Cup brilliance. The Thai doubles pairs played quite well, particularly the team of Narong Bhornchima and Raphi Kanchanaraphi who won both of their matches. Doubles victories were not enough, however, as Indonesia retained the Cup 6–3.