Xavier Marshall, the former West Indies batsman who made his USA debut in January during the CWI Regional Super50 tournament in Antigua, has been left out of a list of 33 players invited to a senior-team selection camp to be held from June 21-24 in Houston, Texas. Marshall is the only player from the 15-man squad that toured the West Indies to not receive an invite to this weekend's camp.

Marshall, 32, began his USA career with scores of 40 and 51 in his first two innings of the Super50 against Leeward Islands and Guyana, but only managed 46 runs combined in his last six innings of the tournament. Ahead of the Super50, Marshall had told ESPNcricinfo that one of his goals was to gain a contract in the Caribbean Premier League (CPL). Even though it is mandatory for each of the six CPL franchises to draft a USA player - or retain a Canada player from 2017 - Marshall was not one of the six USA players taken in the 2018 CPL draft.

All 33 players invited to this weekend's camp took part in one of eight regional combines organised through the spring by USA Cricket. Marshall had attended the New York Combine that took place from May 31 to June 3, top-scoring with a half-century in the T20 trial match that was held on June 1. However, he failed to show up the following two days to participate in two 50-over trial matches.

Instead, Marshall chose to play two club matches over that weekend, in New Jersey for Somerset Cavaliers and New York for Villagers Social & Athletic Club. Marshall's absence on the final day of the New York Combine in particular was a hot-button issue. According to USA Cricket officials who were on site at the regional combine in New York, Marshall called in the morning to say he was on his way to Van Cortlandt Park in the Bronx where the trial was being held, but allegedly called back later to say he could not get a ride from his home in Long Island. However, he showed up later in the morning at Roy Sweeney Park in Queens to play for Villagers.

Gajanand Singh was another noteworthy name to not receive an invite to the final squad trial this weekend in Houston. The 30-year-old former West Indies Under-19 batsman played last season for Guyana Amazon Warriors in the CPL, scoring 151 runs in 11 matches to finish fourth on the team's run-scorers' list, and was retained by Warriors for 2018 after being taken in the 13th round. Gajanand is understood to be a US resident and attended the New York trial, top-scoring for his side in the T20 trial match. However, like Marshall, he no-showed on the last two days, choosing instead to play club matches for Somerset Cavaliers in New Jersey on each day.

Former USA captain Steven Taylor, who is currently contracted with Jamaica in the West Indies first-class franchise system, has been invited to the squad camp in Texas. Taylor, 24, attended the New York Combine but has not played for USA since 2017 WCL Division Three in Uganda, after which he and USA Cricket administrators came to a mutual decision to have him step down from captaincy following his decision to relocate to Jamaica upon taking up a professional contract.

Four uncapped players who rose to prominence during the regional combines and received invites to the USA squad camp for the first time are Tirth Patel, Akshay Homraj, Kyle Phillip and David Wakefield.

Tirth, 20, was one of the leading wicket-takers at the New York Combine and is a former Ahmedabad Under-19 left-arm spinner currently attending university in Ohio. Tirth played for Ahmedabad Under-19 as recently as June 2016 and, as a result, it is unclear if he will be eligible to qualify under the ICC's three-year residency rule to play for USA this year at their next two assignments - the 2020 ICC World T20 Regional Qualifier from September 16-23 and WCL Division Three later in the year. Homraj also competed at the New York Combine and formerly represented Guyana Under-19s in 2014.

Phillip, 21, is a tall fast bowler currently residing in Florida after migrating from Trinidad & Tobago in 2016. He impressed at the regional combine held at the Central Broward Regional Park in Lauderhill, Florida from May 3-6. He was recently signed up by Winnipeg Hawks in the Global T20 Canada draft, one of the only three USA-based players to be roped in along with captain Ibrahim Khaleel and fast bowler Ali Khan.

Wakefield, 23, was born in North Carolina but raised in New Zealand and played for Canterbury Under-19s. The right-hand batsman is still based in Christchurch but paid his own way to attend the USA Cricket regional trial in Florida this May where he scored a pair of half-centuries in the two 50-over trial matches. He would qualify to play for USA automatically as a US citizen and passport-holder from birth.

In addition to the 33 senior men's players invited to the camp, six junior players have also been given the opportunity to attend the camp in order to immerse them early on into the national team set-up. The players will take part in a series of T20 and 50-over trial matches at Smart Choice Moosa Stadium in the Houston suburb of Pearland. A 14-man squad is expected to be chosen following the camp for USA's next assignment, the World T20 Regional Qualifier that USA is hosting in September where they will take on Belize, Canada and Panama.

Peter Della Penna is ESPNcricinfo's USA correspondent @PeterDellaPenna