Greece may prove to be a temporary influence but it's likely to again dominate trading Tuesday, as traders watch the fallout in the oil market and elsewhere.
Stock futures were slightly higher, after Monday's decline. Treasurys were well bid, and there was market talk of hedge fund buying in the 10-year, taking the yield to 2.24 percent in morning trading. Oil was slightly higher after Monday's wild selloff.
The euro area heads of government were meeting Tuesday and Greece was expected to submit new proposals to meet its bailout terms.
Read More Few changes in new Greek proposal
"It'll certainly be Greece unless things melt down further in China. Then that one will come to the top," said Randy Frederick, managing director of trading and derivatives at Charles Schwab.
China's emergency measures to stop the decline in its volatile equities markets were a major undercurrent in markets Monday, as headlines on Greece sent repeated ripples through global financial markets. Shanghai stocks fell another 1.3 percent Tuesday.