And with leaders Sunderland being beaten by Reading, the race for the Premiership is still very much alive with less than a month of the season left.
Jewell will watch Ipswich's visit to Molineux on television, hoping Glenn Hoddle's men can do his side a huge favour.
He said: "This time last week we were on the floor with disappointment but now the pressure – if that is the right word – is back on Ipswich.
"They go to Wolves needing to get something from the game to go back above us into second place.
"I would rather still be in Ipswich's position because at the moment their destiny is in their own hands.
"What we have to do is keep getting as many points between now and the end of the season and hoping it's enough.
"I've said before and after every game that it is going to go right down to the wire because this league has proved so topsy-turvy.
"I think our win against Cardiff means we are definitely in the play-offs.
"For a club like Wigan to have come from where we've been and already be guaranteed the play-offs is an amazing achievement.
"Of course we are trying to get promotion straight off but the players deserve a big pat on the back for getting us where we are now.
"There will be disappointment if we don't go up automatically after being up there for so long but let's look at the bigger picture.
"We are pleased with the progress the club has made although we are never satisfied and always want to do better."
Jason Roberts and Alan Mahon were on target at Ninian Park with second-half goals as Latics ground out the victory over Cardiff.
The starting line-up saw a start for Brett Ormerod with Nathan Ellington switched out to the left wing, while there were recalls for Steve McMillan and Jason Jarrett.
McMillan hadn't started a league game since February last year while Jarrett had to go back almost 12 months for his last start in Wigan colours.
"I just thought we would freshen things up a little bit because the players have played a lot of games this season," said Jewell.
"The lads who came in did exceptionally well and can be pleased with their displays.
"It was a scrappy game to say the least but this was a major result without us every playing free flowing football.
"You're not going to get good games at this stage of the season, and both ourselves and Cardiff are fighting for our lives at different ends of the table.
"I thought we actually did better against West Ham last week than we did at Cardiff but we got three points.
"The first half was almost split in two – we controlled the first 20 minutes without really looking like scoring.
"Then all of a sudden Cardiff got a bit of impetus and put us under pressure.
"There were a couple of corners and skirmishes, one off the line, but we came through that without conceding.
"We scored a great goal early in the second-half – it was a good ball from Steve McMillan and a great header from Jason – and I was even more relieved to see the second go in near the end."
Jewell felt Graham Kavanagh had handled the occasion well, returning to Cardiff just six weeks after his £350,000 transfer to Wigan.
But there was an anxious moment for the midfielder when he received a stern warning from referee Grant Hegley for a foul after he'd already been booked.
"The crowd gave Kav a good reception and he has obviously been a good player for them," said Jewell.
"That was shown at the end when even though Cardiff had lost, their fans showed their appreciation for him which was nice.
"Kav is a good player and a good pro.
"The ideal scenario for him is for us to go up and Cardiff to stay up which I think they will."