If Apple does indeed report iPhone sales in line with analyst expectations of 66.5M units, the company could be closing in on the market share lead Samsung has held in the smartphone market since 2011, reports the WSJ.

Research company Canalys notes that Apple’s anticipated growth in iPhone sales coincides with a dramatic drop in sales of Samsung smartphones.

While that still leaves Samsung well ahead for now, it’s a trendline which could see Apple regain the lead it once held … 

Samsung’s share has been falling, hurt by lackluster sales of its flagship models and the rise of homegrown brands in fast-growing emerging markets. In the third quarter, Samsung shipped about 78 million smartphones, about 25% share of the global market, down from 34% a year earlier, Canalys said.

Apple is expected to announce its most profitable quarter ever later today, thanks to record iPhone sales generated by demand for the larger-screened iPhone 6/Plus.

While the first quarter after an iPhone launch usually marks a peak in sales for the year, Samsung is coming under increasing competition from Chinese manufacturers like Xiaomi, while Apple is seeing its Chinese sales grow. Analysts expect Apple to have sold more iPhones in China than in the US during Q1.

While Apple and Samsung are rivals in the smartphone market, the two have a close relationship in the supply chain, with Samsung expected to make the majority of the A9 chips for the next-generation iPhone.

“It’s going to be closer than it’s ever been since Samsung took the lead,” said Chris Jones, principal analyst at Canalys.