Best backed up his right-side winger Dominic Young in a length-of-the-field try in the 74th minute on Sunday, collecting his pass and racing the final 35 metres to the goal posts at the southern end.
It provided the one real bright moment in a match plagued by bad weather and plenty of handling errors from both sides.
"I feel like I'm saying the same thing every week, I'm just happy to get the win," Knights coach Justin Holbrook said after the match.
"We had to adapt on the run, and the weather came in, and we made it hard for ourselves.
"We weren't doing a lot great until Dylan Lucas had a nice individual moment to get us back in it."
Wests Tigers appeared to have the better momentum at times, which frustrated coach Benji Marshall.
"Disappointed, because for most of that game I thought we were the better team," Marshall said.
"A couple of key moments in the game are hurting us … the fact we couldn't ice that game given the possession we had, the good sets we had."
Scores were locked at 6-6 for most of the second half after the Tigers led 6-0 at the break, bu the Knights found a way to win.
It took 53 minutes before Newcastle finally posted their first points, when Lucas ran on to a nice pass from fullback Kalyn Ponga pass and dodged tacklers to the line.
Young threatened with several busts in his 195 metres and two line-breaks, but nothing came of his earlier flair until Best's support-play moment late in the game.
Despite their unconvincing win, Newcastle have moved up from eighth to fifth on the ladder.
Ponga solidified his position in the Queensland Origin side for the July 8 decider. He was involved in most of Newcastle's attacking moves, before cutting loose after halftime.
He chased down winger Heamasi Makasini to end his 70m dash towards the line, then pounced on a loose ball in another try-saving move a set later.
Ponga also had a line break, busted out of four tackles in his 18 runs, and had an assist for NSW Origin forward Lucas to score his eighth try of the year.
Wests Tigers welcomed back Adam Doueihi, who had missed eight weeks with a shoulder injury.
It only took 10 minutes for the crafty No.7 to prove his value, making a one-on-one steal off Dane Gagai in full flight, before he held up the pass perfectly in the ensuing set for second-rower Tony Sukkar to score his first NRL try in 20 appearances.
Doueihi converted and the visitors were out to a 6-0 lead.
That remained the score at halftime, after both sides showed little intent with the ball. A heavy downpour in the break created a far more slippery surface in the second half.
The Knights, who haven't lost at home since being beaten by the Panthers in round eight, now command a 6-2 winning record in Newcastle this season.
That could be tested next Sunday when they face the fast-swimming Dolphins, who are on an eight-game winning streak.
Wests Tigers travel to Kogarah to face St George Illawarra on Saturday.
11°C