After bundling out UP for 226 in response to their first innings score of 272 at Green Park, the Harbhajan Singh-led Punjab continued to dictate terms and stretch the second-innings lead to 290.
The visitors lost a couple of early wickets, but the 124-run third-wicket partnership between Uday (89 not out) and Mandeep (84) raised trouble for the Suresh Raina-led side.
If Day has stayed patient in his 185-ball stay so far, Mandeep looked devastating during his 101-ball knock that was laced with 12 fours and a six.
Praveen Kumar and Ankit Rajpoot have picked two wickets each.
Earlier starting the day on 208 for eight, the UP innings folded early with Umang Sharma remaining the top-scorer with 49 runs.
Siddharth Kaul bagged four wickets while Harbhajan Singh picked three.
Brief Scores:
Punjab 1st Innings 272 and 244/6 in 73 overs (Uday Kaul 89 not out, Mandeep Singh 84; Praveen Kumar 2-59, Ankit Rajpoot 2-52)
