The Reds have scored only four league goals so far this season - only crisis hit League One side Bolton have scored less in the EFL (2)
Barnsley are the only side in the top four tiers of English football yet to score on their travels.
They have now also failed to score in six of their past nine trips to the City Ground.
Four goals scored from eight league games is Barnsley's lowest at this stage of a season since 2008-2009 (also 4 from 8)
The Reds have gone three games without a goal overall for the first time since November 2017.
A Barnsley game was goal-less at half time for the third successive time - the first time this has occurred since March when two of those games finished 0-0 and the other was won by Barnsley in the final minute.
That victory is the last time Barnsley have won a game that was goal-less at half time - failing to win four since (DDLL)
Jordan Williams and Aapo Halme were booked in the game, meaning that a defender has been booked in every Barnsley match this season except the defeat at Sheffield Wednesday.
Williams was subbed after 71 minutes with his replacement Conor Chaplin also going on to be booked, the first time a player and his replacement has been booked since both Cauley Woodrow and replacement Mike Bahre were booked against Scunthorpe in February.
Chaplin is the first Barnsley substitute to be booked in a league game this season.
Ben Watson scored the decisive goal - his first since April 2016 when he netted for Watford at West Brom. This was however his fifth goal against Barnsley, having also netted in a 4-0 Wigan win in August 2013, 5-2 QPR win in September 2009, and twice in a 3-0 Crystal Palace win in October 2008.
Barnsley's winless run in all competitions stretches to eight (D2 L6), their worst run since November/December 2017 (10 - D4 L6)
Barnsley have lost five of their first eight league games, just as they did in 2017-2018 when they were relegated from the Championship - however their record at this stage then was W2 D1 L5, compared with W1 D2 L5 now.
They have won only one of their first nine in all competitions for the first time since 2013-2014 when they won only one of the first 13.
The Reds have now won just four of their past 28 games at Championship level (D8 L16)
This is the first time Barnsley have won their first league game of the season but then failed to win any of the next seven since 1971-1972 when after opening a Division Three campaign with a 4-2 win over Walsall they failed to win any of their next 13 league matches - they were relegated at the end of that campaign.
Despite failing to score on the road this season, Barnsley have enjoyed more possession than all their opponents bar Wigan who they shared 50% with (64% at Wednesday, 64% at Birmingham, 52% at Forest)
There were just six shots on target in the game, the lowest in a Barnsley match this season and lowest since the home game with Sunderland in March (5)
18 corners were awarded, the most in a Barnsley game this season and most since the first home game of 2017-2018 against Ipswich (also 18)
10 of those were for Barnsley, their most away from home since January at Wimbledon (also 10)
40. Brad Collins
2. Jordan Williams
6. Mads Andersen
24. Aapo Halme
23. Dani Pinillos
21. Toby Sibbick
27. Alex Mowatt (C)
7. Jacob Brown
16. Luke Thomas
36. Mallik Wilks
9. Cauley Woodrow
11. Conor Chaplin (for Williams 71)
19. Patrick Schmidt (for Woodrow 71)
8. Cameron McGeehan (for Halme 77)
10. Mike Bahre, 13. Jack Walton, 22. Clark Oduor, 26. Mamadou Thiam.
Nottingham Forest Team
30. Brice Samba
11. Matty Cash
20. Michael Dawson (C)
4. Joe Worrall
2. Yuri Ribeiro
8. Ben Watson
21. Samba Sow
23. Joe Lolley
28. Cassama Ivanildo
10. Joao Carvalho
7. Lewis Grabban
37. Albert Adomah (for Ivanildo 60)
19. Sammy Ameobi (for Carvalho 70)
17. Alfa Semedo (for Lolley 81)
3. Tobias Figueiredo, 13. John Bostock, 18, Jack Robinson, 49. Arijanet Muric.
Nottingham Forest manager Sabri Lamouchi said:
"We suffered a lot in the game, but I do not mind this when we come through the game with three points.
"The Championship is so, so tough. There are no weak opponents. We respected Barnsley today. We did not score in the first half, when we deserved to.
"It was not a fantastic performance, but it was a good result. We have a lot of experienced players and we cannot accept what happened in the final stages, when we did not control the game.
"We need to work. It was a good result. If we play like this and we win matches? I will sign up for that right now."
Sky Bet Championship results:
SATURDAY 21ST SEPTEMBER
Leeds United (1st) 1-1 Derby County (18th)
Lowe og 20
Birmingham City (11th) 0-1 Preston North End (3rd)
Brentford (17th) 0-0 Stoke City (23rd)
Bristol City (7th) 0-0 Swansea City (2nd)
Cardiff City (13th) 1-0 Middlesbrough (15th)
Fletcher og 2
Luton Town (21st) 0-3 Hull City (14th)
Potts og 90
Millwall (16th) 1-2 Queens Park Rangers (5th)
Nottingham Forest (6th) 1-0 BARNSLEY (22nd)
Reading (20th) 1-2 Blackburn Rovers (10th)
Sheffield Wednesday (9th) 1-1 Fulham (12th)
Wigan Athletic (19th) 2-0 Charlton Athletic (8th)
SUNDAY 22ND SEPTEMBER
West Bromwich Albion (4th) 4-2 Huddersfield Town (24th)
Barnsley lie in 22nd place in the Sky Bet Championship with 5 points from 8 games. We are 10 points outside the Play-Offs, 12 points outside the Automatic Promotion Places, 12 points outside First Place and 2 points inside the Relegation Zone.
Up to 23/9/19
Sky Bet Championship Matchday Nine: Barnsley v Brentford, Sunday 29th September 2019. Kick-Off: 1:30pm
On The Road:
Sky Bet Championship Matchday Eleven: Preston North End v Barnsley, Saturday 5th October 2019. Kick-Off: 3pm