Four out of six ECB Yorkshire Premier League matches were abandoned due to heavy rain and thunder but, crucially, Barnsley lost their narrow lead to York.
They managed to secure a five-wicket victory at Hull whilst the long-time leaders could only watch the rain from the Weetwood dressing room.
The Yorkshire Academy chose to bat against Barnsley and Ben Ainsley (50) and former Collegiate opener Eliot Callis (73) put on 115 for the first wicket before a fine spell by Steve Nuttall, who took 4-54, restricted the youngsters to 246-7.
Jon Trower passed 1,000 runs for the season when he hit 39 in the Barnsley reply, before rain called a halt after 25 overs with the score 86-1.
Collegiate looked well set for victory at Saville Park when, after winning the toss, Castleford were reduced to 109 all out thanks mainly to an outstanding spell of quick bowling by reliable Luke Shutt (6-32).
David Wainwright hit 68 for the home team but no other batsman reached double figures and although Collegiate lost two early wickets, they looked well set for victory when the match was called off at 29-2.
Sheffield United skipper Lesroy Weekes took 5-20 from 10 hostile overs to leave Driffield struggling at 69-6 after they won the toss and elected to bat at Kings Mill Road.
A late rally took the hosts to 155 all out but United, at teatime, looked well set for victory.
Jaco Scholtz, who took four catches in the Driffield innings, again dominated the bowlers and took his total for the season to 902 but he received little support and after he was out for 80, United collapsed from 102-3 to 140 all out.
Rotherham Town’s Mark Cummins took his total wicket haul to 51 when he returned 4-64 against Harrogate at Clifton Lane. But the visitors’ 280 all out gave them the edge when rain called a halt with Town on 27-0.
Cleethorpes were all out for 170 in the 53rd over and the match was delicately poised, with Doncaster on 53-3, when the predicted rain arrived.
Table: York 119, Barnsley 117, Harrogate 106, Rotherham 96, YCA 89, App Frod 73, Driffield 66, Cleethorpes 66, Doncaster 64, Collegiate 55, Castleford 55, United 50, Hull 28.
n Fixtures, Saturday: Barnsley v Doncaster, Driffield v YCA, Harrogate v Cleethorpes, Collegiate v Hull, United v Castleford, York v AppFrod.
n Bank Holiday Monday: Cleethorpes v United, Doncaster v App Frod, Collegiate v Barnsley, Hull v Driffield, Rotherham v YCA, York v Castleford.
n Barnsley chose to bat at Weetwood in the Yorkshire Premier League KO Cup semi final but, after 11 overs, they were in deep trouble at 26-5 and subsided for 132 all out. The Academy knocked off the arrears in 31 overs and now face York in the final.