The Sharks have overcome a half-time deficit to down the Broncos 13-6 in an error-riddled encounter played in strong rain and gusty winds at Toyota Stadium on Saturday night.
The Broncos went to the half-time break with a 6-4 advantage despite having the lion's share of possession, but the Sharks scored nine unanswered points in the second stanza as the Broncos imploded through a string of errors and poor last tackle options.
A clearing kick that went out on the full from Broncos centre Joel Moon put the visitors under pressure early in the second half, with a penalty goal from Covell leveling the scores in the 48th minute, following an offside infringement from Brisbane.
The Broncos continued to shoot themselves in the foot in a very un-Brisbane like performance. They knocked on in their own end, and from the resulting scrum, a cleverly worked scrum play provided Brett Kearney with a four-pointer to give the Sharks the lead for the first time in the match.
Covell nailed the conversion to make it 12-6 to the Sharks after 53 minutes, before Kimmorley's 76th minute field goal killed off the contest.
Sloppy ball handling from the Sharks in wet and windy conditions gave the Broncos a mountain of first half possession, and some extremely lax defending almost gifted the Broncos a simple opening try.
Shane Perry launched a fairly innocuous last tackle bomb, but amazingly, Bronco Nick Kenny was given an uncontested catch at the ball, and looked set to score before a desperate strip from Brett Kearney let the Sharks off the hook.
But the home side continued to invite the Broncos into their own end, and finally cracked in the 18th minute, a clever grubber into the in-goal from Michael Ennis was fallen on by Tonie Carroll for the opening points.
Ennis slotted the straightforward conversion to give the underdogs a 6-nil advantage.
An undisciplined ruck penalty from Ennis turned the flow of the match in the shadows of half time, the Sharks hitting back when Misi Taulapapa latched on to a Brett Kimmorley cut-out pass to go over in the corner.
Luke Covell's conversion attempt from out wide was waved away, the Broncos taking a 6-4 advantage at half time.
Aided by a strong breeze, the Sharks started the second half on fire, Brett Seymour sliced straight through some flimsy Brisbane defence, and the former Bronco seemingly just had to find Kimmorley to put the Sharks ahead in the 42nd minute, but Kimmorley couldn't handle the pass.
Despite a glut of possession and field position, the Sharks were unable to finish off the Broncos, and the Brisbane side kept coming, but the impressive Sharks defence held firm to register a deserved win in the absence of Origin stars Paul Gallen and Greg Bird.
