Sijsling came away a 7-6 (7-3), 4-6, 6-4 winner with just one break but it decided the third set and the match. Tsonga pounded out 14 aces -- against no double faults -- but only finished off one of his eight break opportunities.
Both players won 68 percent of their points on serve and Sijsling had the slightest -- 104-103 -- edge in total points. He had a biggest advantage, however, in the third set when he dropped just seven points on serve.
Victor Hanescu and Nikolay Davydenko also advanced with upsets. Hanescu was a 7-6 (7-4), 6-3 winner over No. 7-seeded Jerzy Janowicz by finishing off the only break of the second set. Davydenko eliminated eighth-seeded Florian Mayer 6-3, 6-2 by converting five of his six break chances. Davydenko won nearly 60 percent of the points off Mayer's serve.
No. 5 Gilles Simon was the only seeded player to advance Monday, getting past Daniel Brands 7-6 (7-3), 6-4. Simon dropped his serve twice but still won 70 percent of the points on serve.