Factbox- Three to watch as Sony changes guard

Kazuo Hirai, incoming CEO of Sony, has his work cut out as he vows to urgently turn around the loss-making Japanese electronics giant.

Hirai replaces Briton Howard Stringer on April 1, and will look to regain Sony's innovative flair, which has waned as Apple and Samsung Electronics have forged ahead. As Hirai prepares to assemble his new team, here are three key executives to keep an eye on: Tadashi Saito, executive vice president Saito, 58, oversees Sony's microchip operations. Products under his supervision include CMOS sensor chips, which meet strong demand as an "eye" for digital cameras. He has extensive overseas experience and once worked as chief financial officer at US unit, Sony Electronics Inc. Saito, who has mostly been with Sony's corporate planning division since joining the company in 1976, becomes chief strategy officer on April 1. Hiroshi Yoshioka, executive deputy president Yoshioka, 59, was one of the "Four Musketeers" picked by Stringer in 2009 as his potential successors. Hirai was also among the chosen four. A 33-year company veteran, Yoshioka is currently in charge of Sony's professional-use gear, such as TV cameras for broadcasting stations, and electronic devices, including microchips. An engineer by training, Yoshioka made his name by spearheading the successful formation of a mobile phone joint venture with Sweden's Ericsson . Sony said in October it was taking over the venture for $1.5 billion, seeking to exploit its music and video to help it catch smartphone leaders Apple and Samsung. Yoshioka later headed Sony's struggling TV operation, where, as others before him, he failed to make the business profitable. Masashi Imamura, senior vice president Imamura, 55, has helped Sony's camera and camcorder division grow into its major and stable cash cow operation by developing popular Cyber-shot digital cameras and Handycam camcorders. Like Saito, Imamura once worked at Sony Electronics Inc. He now oversees the TV operation, the top priority among the businesses that need fixing.