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After 36 holes of golf's final major of the year, the PGA Championship, Americans Jimmy Walker (top) and Robert Streb (bottom) share the lead at -9.

Walker followed up his opening round 65 with a 66, while Streb shot a major record-tying 63, including a birdie on 18 to join Walker in the final group tomorrow.

Defending champion Jason Day shot -5, 65 to tie for second with Argentina's Emiliano Grillo at -7 overall.

Round 3 begins at Baltusrol CC in New Jersey tomorrow morning.

Round 2 Leaderboard: