Kansas University’s softball squad had a bittersweet Sunday.

Hours after completing a regular-season-ending sweep of Iowa State to cap a fourth-place finish in the Big 12 race, the Jayhawks learned only the top three league teams had made the NCAA Tournament. Oklahoma, Baylor and Texas earned NCAA regional bids.

Kansas ended its season with a 12-3, five-inning rout of Iowa State on Sunday in Ames, Iowa.

Held scoreless through the first two innings, KU (34-16, 9-8) scored four runs in each of the next three innings to subdue the Cyclones (21-34, 4-14).

Kansas’ .680 winning percentage was its best since 1992 (.818), and KU finished with a winning Big 12 record for the first time since 2005, when KU also went 9-8.

“We’re really proud of that,” KU coach Megan Smith said. “We started out in last place four years ago and spent a couple of years there. We’ve been making strides, but haven’t been able to take that step in conference. I think this year we sent that message that we’re competitive and we can compete with everybody. I’m really proud of our girls and the hard work they’ve put in.”

Senior left fielder Maggie Hull went 3-for-4 for the second straight game and racked up her 49th and 50th career doubles in the process. The Jayhawk senior finished the regular season by crushing her own KU batting average (.409, 2012) with a .456 mark in 2013. Hull also became the program’s career batting average leader as her .368 mark, established over 210 consecutive starts, makes her the best hitter in Kansas softball history. She passed Becky Ascencio’s previous record of .355 (1982-83).

Fellow senior Mariah Montgomery also started her 210 consecutive game and had a hit. Neither she nor Hull collected an RBI, leaving the school RBI record in Hull’s hands with 140, with Montgomery second at 138.

Sophomore designated player Maddie Stein tied her career high with four hits in four at-bats against the Cyclones, driving in three RBIs to end the regular season as KU’s RBI leader with 49.

Freshman Kelsey Kessler (12-6) made her third appearance of the weekend. The rookie picked up her fourth straight victory in the circle. She shook off a solo homer in the third and back-to-back solo shots in the fourth to hang on for the win. Kessler walked one and struck out six in her 10th complete game.

Kansas 004 44 — 12 15 0

Iowa State 001 20 — 3 4 2

W — Kelsey Kessler, 12-6. L — Tori Torrescano, 11-16.

2B –Maggie Hull 2, Kansas. HR — Chaley Brickey, KU; Torrescano, Aly Cappaert, Maddie Reese, ISU.

KU highlights — Maddie Stein 4-for-4, 3 RBIs; Hull 3-for-4, 3 R; Chanin Naudin 2-for-4, 2 R, 3 RBIs; Ashley Newman 2-for-4, RBI; Mariah Montgomery 1-for-3, 3 R.