Rozner made two birdies in his final three holes to catch first-round leader Jarvis in South Korea at Woo Jeong Hills on Friday.
The South African mixed four birdies with 14 pars to set the clubhouse target with a bogey-free 67, strengthening his bid for a third victory of the season that would lift him to second on the Race to Dubai Rankings.
But Rozner produced one of the rounds of the day late in the afternoon to draw level at the halfway stage, carding a flawless six-under 65.
"I think the two days were pretty similar in terms of ball-striking and scoring," said Rozner.
"I played pretty solid overall. I missed a few greens here and there, but my chipping has been really good this week so far. My putting inside ten feet is very solid as well.
"So I think it's very solid overall. I'm very pleased, very happy with the score and the position I'm in."
Earlier, Jarvis had continued his impressive form after beginning the day with a one-shot lead.
Starting on the tenth tee, he opened with seven consecutive pars before birdies at the 17th and 18th saw him turn in 33.
He maintained that momentum on his second nine, converting strong iron shots into birdies at the third and fourth before parring his way home to sign for a bogey-free round.
"I mean, it's been pretty solid," said Jarvis.
"I felt like I've hit some quality golf shots and rolled in some good putts, enjoying the fans out there.
"There's a few following Si Woo, so yeah, it was pretty nice and the food's unbelievable in this country as well, so yeah, I'm enjoying it.
"Yeah, I'm very proud of myself. I went bogey-free today, which is nice. I mean, I felt like I've just been really solid.
"I haven't been taking on the flags too much and kind of just hitting it onto greens and trying to make the long ones. Yeah, it's been good."
Jarvis and Rozner sit three shots clear of a group of four players, including Open Champion Ryan Fox, DP World Tour winner Martin Couvra, as well as Korean Tour Order of Merit leader Sanghun Shin and Italian Filippo Celli.
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