nifty respected the levels mentioned in analysis yesterday. there is significant Put buildup and we could see a short covering rally, particularly in 2nd half on account of finnifty monthly expiry. going by finnifty OI data, finnifty could close between 18300-18350 ie over 50-100points up. this indicates a good short covering possibility hence nifty could once again touch 17900 intraday. we could see a flat to slight gapdown opening the retest at 17800 levels before rebounding to 17900 levels. 17880/17900 remains major resistance.