Rio de Janeiro, Aug 1 (IANS): Belgian striker Romelu Lukaku, who recently joined Manchester United, could be an "excellent signing" for the Old Trafford club, former full-back Rafael feels.

"I've seen Lukaku play at Everton and a bit at Chelsea," the Brazilian told Omnisport.

"I saw him also when we were champions, and he was in West Brom, (which was) may be my best time in Manchester," Rafael, who now plies his trade for French outfit Lyon, said.

Since joining United ranks, Lukaku has impressed his manager Jose Mourinho with strong displays during their tour of the United States, scoring in friendlies against Real Salt Lake, Manchester City and Valerenga.

Lukaku finished second on the Premier League scoring charts with 25 goals last season behind only Harry Kane's 29.

"For me, he is a good player and is at a good age, an age he can evolve, but if he keeps what he did last year and in the last two or three years, he will be an excellent signing."

Moving on, Rafael also spoke on his former teammate at Lyon Alexandre Lacazette's move to Arsenal, saying he would adapt to life in England quickly.

"I admired and still admire his football a lot," Rafael said.

"He is a very smart player, he knows how to score. He's fast, and that's all an attacker needs. I think he will do very well at Arsenal."

"I guess so [he'll need to adapt] and I think it will not take that long. In the early games, he could struggle a little, but it will be fast," Rafael was quoted as saying by ESPNFC.

Lacazette scored in Arsenal's 2-1 loss to Sevilla.

Rafael, 27, has spent seven years at United making more than 100 appearances for the club.