The Blues were 13 without after starting their chase for an unreachable chase for 546 with just the last day remaining.
Sialkot, who had taken lead of exactly 100 runs on the first innings, piled the runs at will to reach 445 all out with six of their batsmen crossing 40.
Adeel Malik, younger brother of Pakistan all-rounder Shoaib Malik, struck 15 fours in scoring 79. Ayub Dogar (73), Faisal Khan (72) and Nayyar Abbas (66) all made significant contributions to bat Karachi Blues out of the match.
Tanvir Ahmed (4-100) and Tariq Haroon (4-158) were the chief wicket-takers.
Karachi Whites, meanwhile, were course to defeat Sui Southern Gas Company (SSGC) after closing at 175-2 in pursuit of a modest 223-run target at the Southend Cricket Club Stadium. Opener Mohtashim Ali (75) and skipper Afsar Nawaz (57) have so far added 97 for the unbroken third-wicket partnership.
Earlier, Rizwan Ahmed failed to score century in each innings by only eight runs as he was left stranded on 92 (126 balls, 15 fours) when SSGC's final wicket fell at 182. Rizwan made 113 in the first innings.
Khan Research Laboratories (KRL) saved themselves from relegation with a three-day defeat of Pakistan Customs at the KRL Stadium in Rawalpindi.
Needing 159 for just their second victory this season after Customs were bowled out for 137 in the second innings, Saeed Anwar (79 not out) and Sohaib Maqsood (71) put KRL on the track with an opening stand of 155.
Our Sports Reporter adds from Lahore Habib Bank's preparations for the trophy final against Karachi Blues ended on a high note as the bankers defeated Lahore Shalimar by a comfortable margin of 117 runs at the Gaddafi Stadium.
The bankers' eighth win in Group 'A', which took their tally of points to 66, was set up by a priceless last-wicket partnership of 92 between former Pakistan pacemen Irfan Fazil (61 not out) and Shahid Nazir (33) that helped Habib Bank to 263 in the second innings.
Lahore Shalimar, who had earned a narrow eight-run lead on the first innings, fell apart for 138 while chasing 256 runs needed for their first win.
Slow left-armer Abdul Rehman sent the selectors yet another reminder for a possible recall to the Pakistan side with 5-36 in 18.2 overs.
Rawalpindi finished their championship campaign with a crushing innings and 25-run win over hosts Multan. The talking point of this game was the outstanding performance put in by emerging paceman Mohammad Rameez.
The former Under-19 World Cup representative, who took 5-86 as Multan subsided to 208 in the second innings, finished with match figures of 13-132.
Lahore Ravi were on verge of completing a big win as Islamabad struggled to 285-8 after being forced to follow on at the LCCA Ground. The visitors, facing a first-innings deficit of 308, still require 23 runs to make Lahore Ravi bat again.
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