SAO PAULO, Feb 17 (Reuters) - Standard & Poor’s downgraded Brazil’s credit rating deeper into junk territory on Wednesday, highlighting the challenges facing President Dilma Rousseff, who is trying to regain investors’ trust and pull Latin America’s largest economy out of recession.

S&P cut Brazil’s sovereign credit rating to BB from BB+ with a negative outlook, just months after a downgrade in September that stripped the country’s hard-won investment-grade rating. (Reporting by Brazil Newsroom; Editing by Chris Reese)