On a bumpy pitch, Stags had a strong wind behind them in the first half. The best early chance fell to Worthing but Dillon Nagle fired wide when it looked easier to score.
Midhurst opened the scoring through Lewis Hyde’s diving header from a corner.
Stags keeper Bird was forced into action with a smart save from Dan Hills.
Worthing had the ball in the net but Callum Thoms’ free-kick was disallowed.
When Liam Dreckmann was caught in possession on the halfway line, Stags defence failed to clear the long ball into the box and it fell to James Thurgar, who levelled in the 36th minute.
Stags saw the half out with Worthing fired up.
In the second half the first big chance fell to Stags forward Marcus Bedford, who was put through from a knockdown by Jake Slater but shot over.
The Stags’ defence stood firm and Harry Giles made a great block to deny the hosts.
Midhurst created some late chances but it went to penalties. Bird saved from Nagle, Greenwood and Thurgar but Bedford,Hyde,Hamilton all converted for the Stags.
Midhurst boss Andy Ewen said: “We weren’t at our best but we stuck together and ground it out. We defended really well in the second half.
“When called upon Josh made good saves and then he stepped up and saved three penalties which was brilliant for him. I’m just really pleased for everyone.”
The final is against Billingshurst at Broadbridge Heath next Wednesday (7.30pm) – fans are allowed.
Arundel Res 0 Unicorn 2
Brad Nixon tucked away two crisp goals to leave the Unicorn as worthy champions at the end of the West Sussex League’s nail-biting supplementary shield.
Both sides went into the final match knowing they had to win to finish top.
The Bognor-based pub side were kicking themselves that they were not already title-holders after leaking a couple of late goals in a 2-2 draw with Lavant after taking a commanding lead through a Tyler Hope penalty and Andy Cox’s slick finish the previous week.
But Danny Towers’ team were determined to make amends against the Mullets and dominated from the start with keeper Luke Munt rarely troubled and Nixon putting the match beyond doubt with his accurate finishing.
“Brad scored a couple of goals that were absolute quality,” said assistant coach Paul Frangou. “He’s a very good striker and his work rate’s phenomenal. When he gets a decent opportunity to score you just know he’s going to finish.
“The whole squad has a winning mentality and we go into every game firmly convinced we are going to win.
“We also have a brilliant backroom staff with chairman David Phills, Guv Slaughter and Dennis Barclay.
“And they’ve transformed the club from a successful Sunday side into an operation which also has a winning Saturday team and a good reserve squad and we are fortunate to be playing home games at Wick’s Crabtree Park.
“You couldn’t ask for more and we’re all very grateful to them for their motivational hard work behind the scenes.”