You are NOT eligible to file for citizenship. The rule requires that you have been a LPR for 3 years and married to a citizen during the same duration. The fact that you have not filed I-751 indicates you have been a permananet resident for only 2 years. Thus , you are not eligible.Intesresting situation! I am about to apply for I-751 as well and since I will be married with a USC for three years by the time apply, I will be eligible to apply US Citizenship. Does that mean I can both at the same time?