Emotional Jason Day breaks five-year PGA Tour drought

Australian golf star Jason Day has broken a five-year PGA Tour title drought with an emotion-charged Mother's Day victory at the $US9.5 million ($A14.3m) AT&T Byron Nelson Championship in Texas.

A year after losing his mum Dening to cancer and tumbling outside the top 100, Day denied Scottie Scheffler the chance to return to world No.1 in a tense Sunday shootout at TPC Craig Ranch.

Day fired a brilliant bogey-free final-round nine-under-par 62 to secure a steely one-shot win over Si Woo Kim (63) and American Austin Ekroat (65).

Kim's countryman CT Pan (62) was fourth at 21 under, with Scheffler (65) ultimately finishing fifth three shots back after being unable to stay with Day down the stretch.

Kim birdied the last to briefly join Day atop the leaderboard but Day held his nerve to respond and deliver his wife Ellie - greenside and heavily pregnant with the couple's fifth child - her own priceless Mother's Day gift.

In a poignant tribute, Day's caddy sported a bib with his mother's birth name "Adenil" and the inspired former world No.1 honoured her memory in style with his first tournament win since the 2018 Farmers Insurance Open.

In a huge confidence booster ahead of next week's US PGA Championship, the season's second major in New York, Day finished at 23 under and had only three bogeys for the week.

Fittingly, the 35-year-old ended his barren run at the same tournament where he clinched his maiden PGA Tour win in 2010.

But his 13th triumph is even more special and completes Day's tumultuous journey back from heartache and despair.

He was languishing at 175th in the world last September before rebuilding his swing to combat the debilitating back injury that threatened to prematurely end a once-great career.

But the 2016 PGA Championship winner's resilience is now paying off, with Day among the hottest players on the planet once more.

He posted six top-10 finishes this year and eight consecutive top-20s before an untimely bout of vertigo cruelled his Masters' chances.

As well as the trophy, the Queenslander pocketed a cheque for $US1.7 million ($A2.6m) after snapping his 1835-day title drought.

Day and Scheffler both started the round two shots behind co-leaders Ryan Palmer, Austin Eckroat and China-born Dallas local Zecheng Dou, who moved clear early on Sunday.

But the cream rose to the top after Dou opened the door with a double-bogey six on the par-4 eighth hole.

Day and Scheffler picked up four shots each to enter the back nine joint top at 18 under, with 22 players within three shots of the lead.

After cruelling hitting the hole with his approach on the 11th and darting off the green, Day had the golfing gods on his side when he chipped in for birdie at the next to claim the solo lead for the first time.

He was never headed, despite Scheffler and company all at times sharing the lead.

Fellow Australian and former world No.1 Adam Scott enjoyed the clubhouse lead for more than an hour at 19 under following an eight-birdie final-round 63.

Scott eventually settled for equal seventh.

Compatriot Aaron Baddeley closed with 68 to tie for 23rd at 15 under, while David Micheluzzi (70) finished at nine under in a respectable share of 67th on his PGA Tour debut.