The yen built further on a round of strong gains since the Bank of Japan meeting, moving to an 18-month high against the dollar.
National Australia Bank's Christy Tan expects the dollar/yen to be at 116 by end 2016, as the BOJ will do more easing to reach its inflation target.
Aviva Investors' Mary Nicola reckons the BOJ wanted to wait and observe the impact of the negative interest rate policy before easing further.
The PBOC guided the yuan higher at the sharpest pace since 2005 on Friday in a move attributed to the dollar's weakness against major currencies.
If the BOJ's priority was to stabilize the dollar/yen, they would have announced something, argues Westpac Bank's Sean Callow.
Eastspring Investments' Nicholas Ferres says the BOJ has effectively tightened financial conditions in Japan by standing pat on policy.
The Nikkei is expected to face downside pressure but that could change if policymakers hint at more stimulus, say AMP Capital Investors' Shane Oliver.
HSBC's Izumi Devalier explains that the BOJ's decision was an unpleasant surprise for markets but that could be because of bigger strategic considerations.
UBS Wealth Management's Hartmut Issel describes BOJ's Kuroda as a central banker who does not like predictability or incremental policy change.
MFS Investment Management's Jim Swanson says central banks need fiscal cooperation and structural reform to support the economy as well.
The BOJ now has a credibility problem, because the conditions for further easing were there but they didn't deliver, says Wells Fargo's Tim Quinlan.
Stocks head into the last day of April in a cranky mood, but May might not be the time for a shakeout.
David Darst, Independent Investment Consultant, talks about the market reaction to the Bank of Japan's inaction and his market theme of the week: M.A.Y.
Gold rose as the BOJ held off from expanding stimulus and the Fed signaled it was in no rush to tighten.
The Bank of Japan became the latest central bank to throw markets a curveball, but what does it mean?
Jack Bouroudjian, Universal Compute Exchange Founder and CNBC Contributor, and Gene Tannuzzo, Columbia Threadneedle Investments Fixed Income Portfolio Manager, discuss the Bank of Japan's affect on markets after leaving policy unchanged.
CNBC's Seema Mody looks at the inaction from the Bank of Japan and how it's affecting stock markets and the yen.
Allianz Chief Economic Advisor Mohamed El-Erian, discusses the relationship between trading and Fed policy.
Allianz Chief Economic Advisor Mohamed El-Erian, says there are few companies that combine platform and content, which is the "most powerful equation."
The Bank of Japan held off on additional stimulus measures, shocking the markets. Allianz Chief Economic Advisor Mohamed El-Erian, provides perspective.