Indian golfers Jeev Milkha Singh and SSP Chowrasia fell further down the ladder with disappointing second round cards in the WGC-HSBC Champions in Shanghai on Friday.
Jeev shot one-over 73 and dropped to one-over 145 for two rounds at tied 53rd place. Chowrasia (74) was down to 63rd with a total of three-over 147.
Sweden's Fredrik Jacobson overcame a two-shot deficit by returning a flawless six-under 66 to take the second-round lead.
Jacobson, who finished third in Malaysia last week, leads by one shot ahead of 2010 British Open winner Louis Oosthuizen who signed for the day's lowest score of 63 to take a share of the second place alongside Australia's Adam Scott on 134.
Among other leading players, US Open Rory McIlroy (70-69) and Masters champion Charl Schwartzel (70-69) - at 139 - were tied 17th.
Three-time Asian Tour Order of Merit winner Thongchai Jaidee of Thailand continued to put Asia in the spotlight with a second round three-under 69. Thongchai posted a two-day total of seven-under 137 to stay four shots back of leader Jacobson. Thongchai was tied seventh. Asian Tour honorary member KJ Choi of Korea also ensured that another Asian player would feature prominently on the leaderboard after returning with a 70. At six-under for 36 holes, he was tied 11th.