1958 Thomas Cup knockout stage

The knockout stage for the 1958 Thomas Cup began on 5 June 1958 with the first-round knockout and ended on 15 June with the final tie.

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

First round
The results of the inter-zone ties in Singapore gave ample evidence of both the growing popularity of the sport in the Far East and the advantage these nations enjoyed competing against "outsiders" in a tropical climate. Showing strength and balance in singles and doubles, Thailand sent the USA home with a 7–2 defeat. A curiously revealing match in this tie was the victory of Thailand's Sunthorn Subabandhu and Kamal Sudthivanich over the strong U.S. veterans Alston and Rogers, 18–14 in the third game after dropping the first game at zero.

More stunning, and ominous for Malaya, was newcomer Indonesia's 6–3 victory over a highly rated Danish contingent. Erland Kops was beaten by both the internationally experienced Ferry Sonneville and by young sensation Tan Joe Hok. Even the powerful Danish doubles pairing of Finn Kobbero and Jorgen Hammergaard Hansen could earn only a split in two matches.

Indonesia vs Thailand
Indonesia went on to comfortably defeat Thailand in the inter-zone final 8–1. In another bad sign for Malaya, Thailand 's top two singles players, Charoen Wattanasin and Thanoo Khajadbhye, respected internationals who had dropped only one singles match between them in the campaign prior to playing Indonesia, were each decisively beaten by both Sonneville and Tan Joe Hok. Thailand won one doubles, though all four of these matches went to three games.

Malaya vs Indonesia
The challenge round played in the middle of June brought Malaya's nine year Thomas Cup reign to an end. With Wong Peng Soon and Ong Poh Lim retired, Eddie Choong's game showing recent vulnerability, and some controversy over the selection of team members still percolating, Malayan confidence might have been low from the start. The three-time defending champions were unable to win any of the singles matches against Indonesia and eventually lost the tie 3–6.

Choong was twice beaten routinely in straight games and was booed off the court by his countrymen. Malaya's other top singles player, Teh Kew San, nearly broke through against Sonneville but finally went down 16–18 in the third. At least one of Malaya's doubles wins appeared to be a gift after the outcome had been determined. Indonesia's Tan Joe Hok went through the entire Thomas Cup campaign undefeated in singles (Sonneville had dropped a match to Finn Kobbero). Tan would win the All-England singles title the following year and for a time would be regarded as the best player in the world. For a much longer time Indonesia would be the country to beat in international team badminton.