Cobblers midfielder Ryan Watson slammed home a well-struck winner just before the half hour mark for the hosts in a forgettable Good Friday clash from a Shrewsbury perspective.
In failing to respond to last weekend’s Portsmouth reverse, it was the first time Salop had lost two League One games on the spin since losing four in a row under former boss Sam Ricketts in October.
Cotterill and Aaron Wilbraham’s men got what they deserved on a disappointing and underwhelming afternoon at Sixfields where a much-changed side, boosted by the return of several key players, failed to deliver.
Town’s last victory in Northampton remains that incredible 7-2 in 2011, and in ending a run of five without defeat here, Shrewsbury did little to boost hopes of a late surge up the table.
Cobblers goalkeeper Jonathan Mitchell did not have a save to make in a huge win for the hosts. Shrews’ decision to leave a triple change until two minutes from time left fans scratching heads.
Still 17th, Town will need to show at home to Plymouth on Easter Monday there is still life in their final 10 games.
Shrewsbury were boosted by significant availability news for their first trip to the PTS Stadium in more than three years.
Defender Aaron Pierre made his return to the backline as one of five changes after exactly two months away at the club at which he was player of the season when Shrewsbury signed him in 2019.
The stopper had missed around a dozen games with a significant calf injury sustained at the beginning of February.
He was joined back in Cotterill’s XI by captain Ollie Norburn, who returned to midfield after serving a two-match suspension for 10 yellow cards.
There were also recalls for No.1 goalkeeper Matija Sarkic, back from international duty with Montenegro, as well as Donald Love - who overcame a groin injury - at right wing-back for his 50th Town appearance.
Harry Chapman was opted in attack, just off frontman Curtis Main. Daniel Udoh was missing from the entire matchday 18.
Relegation-battling Cobblers had improved in recent weeks under caretaker boss Jon Brady, who has been in place since Keith Curle’s February sacking.
Northampton - who began the afternoon outside the drop zone on goal difference - have claimed some impressive scalps recently, but come unstuck against sides around them, notably a 1-0 reverse at AFC Wimbledon last time out.
Brady’s men introduced Leeds loanee Ryan Edmonson for Mark Marshall, who scored in the 2-1 win at Salop in Town’s first home game of the season.
A minute’s silence was immaculately observed ahead of kick-off as the sides remembered the life of Lee Collins, the Yeovil City captain who tragically died this week aged 32.
Collins, who was born in Telford, spent a period on loan at Shrewsbury in 2012 and was captain at Sixfields during his two-year stint between 2013 and 2015.
The hosts were the brighter inside the first 10 minutes and forced a couple of dangerous free-kicks 25 yards from the Town goal. Former Salop midfielder Bryn Morris sent the first wide of the near post and David Davis strongly blocked Watson’s next effort.
Cobblers’ start would’ve encouraged the 20 or so supporters camped at the top of the grass verge that overlooks the Sixfields pitch. Watson sent a speculative, dipping 30-yard half-volley straight down Sarkic’s throat.
A bitty opening quarter was the result of a stop-start contest. Salop, though, did liven up midway through the half, as Main latched on to a Pierre downward header to finish excellently across keeper Mitchell with his weaker left foot.
Unfortunately for the Shrews frontman, the offside flag had been raised.
Shortly afterwards the hosts broke Town’s offside trap and a left-sided cross, headed on by Danny Rose, was met by a sliding Sam Hoskins, whose improvised effort from an acute angle was well kept out down low by Sarkic.
The Cobblers were lively in spells and edged ahead just before half hour.
Adventurous Luton loanee Peter Kioso progressed well done the right and his clever low cross picked out Watson’s unchecked run just inside the box and the attack-minded midfielder finished excellently high into the left corner for his eighth goal of the season, leaving Sarkic little chance.
Unsurprisingly Nathanael Ogbeta led the charge down the left, the teenager bounced through one foul before a powerful cross was headed wide at the near post by Main.
Ogbeta, involved in Shrewsbury’s last four goals, continued to appear the visitors’ main source. A great run and an even better cross was headed over sightly on the stretch by Chapman. It was a decent opening.
Shrewsbury ended the half better and only an excellent, goal-saving challenge from Kioso denied Vela a clear sight at goal from just 12 yards.
Cobblers continued to enjoy themselves on the break, as a route one path released the lively Hoskins, but the retreating Ogbeta did enough to force Hoskins into an early half-volley straight at Sarkic.
Shrewsbury required an injection of guile after the interval and did improve for a period.
Main’s neat ball picked out Love’s overlapping charge down the right. It appeared the full-back, without a goal in 50 Salop games, was free in the box but a fine recovery challenge blocked him. Main sent a header from a corner over the top soon after.
The visitors remained the better side in the second period but a flurry of early efforts on goal in the hunt for a leveller dried away. Vela’s strike over from distance with 20 minutes left rather summed up Town’s efforts.
A lack of options ahead of Chapman were typified when the attacker jinked his way infield before opting to shoot at Mitchell from all of 30 yards. Aside from the disallowed goal, it was Town’s first effort on target, 75 minutes in.
Salop’s decision-making, particularly in the final third, continued to evade them. It was a surprise to see Northampton make the first change, Town reacting with their roll of the dice to introduce striker Rekeil Pyke with 10 minutes left.
Indeed Cobblers could’ve made it two. A poor backpass from Davis was robbed by Hoskins and the Cobblers man charged into the box before striking the side netting from a narrow angle.
The contest limped to a conclusion with blunt Salop unable to come close to threatening the hosts’ clean sheet.
Northampton Town (4-3-3):
Mitchell; Kioso, Horsfall, Jones, Mills ©; McWilliams, Watson, Morris; Edmondson (Sheehan, 79), Hoskins, Rose.
Subs not used: Harriman, Bolger, Chukwuemeka, Berry, Marshall.
Shrewsbury Town (3-5-2):
Sarkic; Williams (Goss, 88), Ebanks-Landell, Pierre; Love, Norburn © (Edwards, 88), Davis, Vela, Ogbeta; Chapman (Whalley, 88), Main (Pyke, 79).
Subs not used: Burgoyne, Sears, Pennington.
Referee: Ross Joyce