The United States and Oman both ensured promotion to Division 3 of the International Cricket Council (ICC) World Cricket League (WCL) by reaching the Division 4 final, which the former won by 13 runs in front of a home crowd at Woodley Park in Los Angeles.
The hosts lost their first three wickets for only five runs before Alex Amsterdam’s 50, Timroy Allen’s 45 and a 37 not out from Jasdeep Singh helped the team put up a competitive total of 208.
Singh later came on to bag three wickets and claim the player of the match award as Oman managed 195-9 in 50 overs.
"This victory means a lot to us, especially as it came with the home crowd behind us," said US captain Steven Taylor.
"It has given us a big momentum.
"Winning this tournament was not easy, no matter what.
"We now want to go on and try to win the next tournament, we want to back our ability."
Oman had won four of their five preliminary league matches, beating Jersey, Bermuda, Italy and Denmark.
Their only loss came against the US and they were unable to avenge it in the final.
"It’s a disappointment because we played well right throughout," said Oman coach Duleep Mendis, a former Sri Lanka captain.
"We beat everyone but lost in the play-off to USA.
"But more than anything else, the mission was to get promoted to Division 3.
"The team worked really hard for the last three months for this."
The US had three players scoring more than 200 runs in the tournament, with Amsterdam, Taylor and Allen managing 213, 209 and 204 respectively.
For Oman, Swapnil Khadiya scored 197 runs in the tournament and Zeeshan Siddiqui managed 192.
Khawar Ali, who scored 168 runs and also grabbed 13 wickets with his leg-spin bowling, was named player of the series.
Denmark and Bermuda remain in the same division, while Jersey and Italy were relegated to Division 5 in a system of continuous promotion and relegation.
This cycle of WCL events provides teams a chance to qualify for the ICC Cricket World Cup Qualifier 2018.
The top two teams from Division 2 will join the top four sides from the ICC WCL Championship and the bottom four sides from the ICC one-day international team rankings.