The 24-year-old showed the UK fans why there is plenty of hype surrounding the Texans quarterback as he threw for 201 yards, which saw him lead his team with two long-distance touchdowns before a late pass to DeAndre Hopkins sealed victory.
Houston came into the AFC South clash with a 5-3 record, while the Jaguars were 4-4 ahead of their seventh appearance at Wembley.
— NFL UK (@NFLUK) November 3, 2019
However, the final game of this season's NFL London series proved to a be a one-sided affair, with the Texans moving top of their division before the Indianapolis Colts travel to the Pittsburgh Steelers on Sunday evening.
Houston opened the scoring as they worked their way down the field but despite a 13-play drive for 77 yards, they only profited with a 52-yard field goal through Ka'imi Fairbairn.
That was the only score of the first quarter but Houston were soon 9-0 ahead at the start of the second when Watson found Darren Fells for his sixth reception touchdown of the season.
Watson orchestrated a superb 80-yard charge downfield in 14 plays but Fairbairn could not add the extras after safety Cody Davis blocked his effort.
Jacksonville finally got on the scoreboard thanks to Josh Lambo's field goal and despite Fairbairn falling short with effort at the other end of the pitch, the Texans led 9-3 at the break.
The Jaguars had a great chance to cut the deficit to three points in the third quarter when Lambo lined up another field goal, only for a mishandled snap which saw the kicker abort his effort and fumble the ball – with Houston taking full advantage.
Fairbairn added a field goal before Watson sent the Texans for a gain of 79 yards in five plays for Duke Johnson to bulldoze his way into the end zone to earn a 19-3 lead at the end of the third quarter.
Jacksonville needed the next score to have any chance of an unlikely comeback but quarterback Gardner Minshew II threw his first intercepted pass of the season after Jahleel Addae picked him off.
Running back Carlos Hyde passed 100 rushing yards in the next play for Houston and looked set to seal victory when he streaked through a gap in the defence, only to see the ball forced out of his hand by Jarrod Wilson just two yards short of the end zone.
The Jaguars reclaimed the ball but Justin Reid intercepted Minshew as they gave possession away once again and Watson ensured that his side were out of sight.
The quarterback was denied a touchdown of his own despite an impressive hurdle over the defence to move Houston to one yard, before he found Hopkins with a flat pass to extend the lead to 26-3.
Minshew fumbled twice in final moments of the match in a desperate bid to close the gap but it was Bill O'Brien's side who improved their record to 6-3 and their chances of making the play-offs.