Updated

East London, South Africa (SportsNetwork.com) - John Hahn fired a 10-under 61 on Friday to vault into a 2-stroke lead at the Africa Open before play was suspended for darkness.

There was a halt in play for an hour and 35 minutes earlier in the day due to heavy rain, which eventually caused the suspension. The second round will resume at 12:15 a.m. ET Saturday.

Hahn, who is seeking his first career victory on the European Tour, finished 36 holes at East London Golf Club at 16-under-par 126.

"I just got the putter hot early and it stayed hot all day. It turned into a good one," Hahn said about his round. "I hit a lot of fairways and greens and the greens I missed early in the round, I got up and down. I made a couple of putts you don't normally make and had a couple of unexpected ones go in."

First-round leader Ricardo Santos carded a 5-under 66 to sit in second place at 14-under 128, while Oliver Fisher shot an 8-under 63 to jump into solo third at 13-under 129.

David Horsey (64) is alone in fourth at 12-under, a shot ahead of Fabrizio Zanotti (66), Lucas Bjerregaard (67), Adam Gee (65), Emiliano Grillo (63) and Thomas Aiken (65).

Hahn started his round on the ninth tee and opened his bogey-free round with a birdie. After parring his next four holes, the American converted another birdie effort at the 14th to move to 8-under.

He would par his next three holes before catching fire at the 18th, recording a birdie at the hole to start a streak of three straight. He did one better with an eagle at the third to pull within a shot of clubhouse leader Santos at 13-under.

A birdie at the fourth gave him a share of the lead, and he quickly pulled ahead with a gain at the sixth. He followed a par at the seventh with a birdie at the eighth to claim a 2-stroke lead heading into the weekend.

Santos also started on the ninth hole and parred his first before recording a birdie at the 10th. He picked up another shot at the 13th to get to 11-under.

Santos later rolled in back-to-back gains at the third and fourth to snap a streak of seven straight pars and reached 14-under with a birdie at the seventh. He parred the eighth to end there.

"I was very pleased to score so well today, I really couldn't ask for much more," said Santos. "There is still a lot of golf to come, but I'm very happy with my position at the moment."

NOTES: Santos was the European Tour's Rookie of the Year in 2012 ... This event is co-sanctioned by the Sunshine Tour ... The cut line currently sits at 5-under 137, with 67 players currently above that line. Wallie Coetsee and Sihwan Kim sit right on the number with three and four holes to play, respectively.